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Expand Up @@ -30,6 +30,10 @@

Baseline Capturing captures queries that meet capturing conditions and create bindings for them. It is used for [preventing regression of execution plans during an upgrade](/sql-plan-management.md#prevent-regression-of-execution-plans-during-an-upgrade).

### BR

BR is the Backup and Restore tool for TiDB. See [BR Overview](/br/backup-and-restore-overview.md) for more information.

### Bucket

A [Region](#regionpeerraft-group) is logically divided into several small ranges called bucket. TiKV collects query statistics by buckets and reports the bucket status to PD. For details, see the [Bucket design doc](https://github.com/tikv/rfcs/blob/master/text/0082-dynamic-size-region.md#bucket).
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The sentence is not clear enough. It is recommended to clarify the relationship between Region and bucket, and to supplement the explanation of how buckets are used.

Suggested change
A [Region](#regionpeerraft-group) is logically divided into several small ranges called bucket. TiKV collects query statistics by buckets and reports the bucket status to PD. For details, see the [Bucket design doc](https://github.com/tikv/rfcs/blob/master/text/0082-dynamic-size-region.md#bucket).
A [Region](#regionpeerraft-group) is logically divided into several small ranges called buckets. TiKV collects query statistics by these buckets and reports the bucket status to PD. This helps in optimizing query performance and load balancing. For details, see the [Bucket design doc](https://github.com/tikv/rfcs/blob/master/text/0082-dynamic-size-region.md#bucket).

Expand All @@ -40,6 +44,10 @@

With the cached table feature, TiDB loads the data of an entire table into the memory of the TiDB server, and TiDB directly gets the table data from the memory without accessing TiKV, which improves the read performance.

### CF

CF is short for Column Family as used by RocksDB / TiKV.
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The definition of CF is too brief and lacks context. It is recommended to provide more information about its role and significance in RocksDB/TiKV.

Suggested change
CF is short for Column Family as used by RocksDB / TiKV.
CF is short for Column Family as used by RocksDB / TiKV. In the context of RocksDB and TiKV, a Column Family is a logical separation within a database that allows for different settings and optimizations for different types of data. This feature enables more efficient data management and retrieval.


### Coalesce Partition

Coalesce Partition is a way of decreasing the number of partitions in a Hash or Key partitioned table. For more information, see [Manage Hash and Key partitions](/partitioned-table.md#manage-hash-and-key-partitions).
Expand All @@ -48,14 +56,72 @@

Introduced in TiDB 5.3.0, Continuous Profiling is a way to observe resource overhead at the system call level. With the support of Continuous Profiling, TiDB provides performance insight as clear as directly looking into the database source code, and helps R&D and operation and maintenance personnel to locate the root cause of performance problems using a flame graph. For details, see [TiDB Dashboard Instance Profiling - Continuous Profiling](/dashboard/continuous-profiling.md).

### CTE

A Common Table Expression (CTE) is part of the SQL standard and uses [`WITH`](/sql-statements/sql-statement-with.md) statements.

## D

### DDL

Data Definition Language (DDL) is the part of the SQL standard that deals with creating, modifying and deleting tables, indexes, columns and other objects.

### DM

Data Migration is the tool that allows MySQL to TiDB migration by reading data from a source instance and applying it to a target MySQL instance. See [DM Overview](/dm/dm-overview.md) for more information.
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The sentence is unclear and could be improved for better readability. It is recommended to clarify the process of data migration from MySQL to TiDB.

Suggested change
Data Migration is the tool that allows MySQL to TiDB migration by reading data from a source instance and applying it to a target MySQL instance. See [DM Overview](/dm/dm-overview.md) for more information.
Data Migration (DM) is the tool that facilitates the migration from MySQL to TiDB by reading data from a source MySQL instance and applying it to a target TiDB instance. See [DM Overview](/dm/dm-overview.md) for more information.


### DML

Data Modification Language (DML) is the part of the SQL standard that deals with inserting, updating and deleting rows in tables.

### DMR

Development Milestone Release (DMR) is a version of TiDB that provides users with the latest features but doesn't provide long term support. See [TiDB Versioning](/releases/versioning.md) for more information.

### DR

Disaster Recovery (DR) describes solutions that can be used to recover from a disaster in the future. This includes things like backups and standby clusters.

### DXF

Distributed eXecution Framework (DXF) is the framework used by TiDB to speedup index creation and data import by distributing tasks over all available resources. See [DXF Introduction](/tidb-distributed-execution-framework.md) for more details
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The sentence is missing a period at the end.

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Distributed eXecution Framework (DXF) is the framework used by TiDB to speedup index creation and data import by distributing tasks over all available resources. See [DXF Introduction](/tidb-distributed-execution-framework.md) for more details
Distributed eXecution Framework (DXF) is the framework used by TiDB to speed up index creation and data import by distributing tasks over all available resources. See [DXF Introduction](/tidb-distributed-execution-framework.md) for more details.


### Dynamic Pruning

Dynamic pruning mode is one of the modes that TiDB accesses partitioned tables. In dynamic pruning mode, each operator supports direct access to multiple partitions. Therefore, TiDB no longer uses Union. Omitting the Union operation can improve the execution efficiency and avoid the problem of Union concurrent execution.

## E

### EC2

Elastic Compute Cloud (EC2) is an AWS service that provides compute resources. This can be used with TiUP to run a TiDB Cluster.

## G

### GA

General Available (GA) is the first non-beta version of a software product.

### GC

Garbage Collection (GC) is the process to cleanup unused resources. See [GC](/garbage-collection-overview.md) for the GC process of TiKV.

### GTID

Global Transactions ID's (GTIDs) are used by recent MySQL versions binary log to indicate what transactions have been replicated and which have not. This information can be used by DM.
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The sentence contains a grammatical error. "ID's" should be "IDs".

Suggested change
Global Transactions ID's (GTIDs) are used by recent MySQL versions binary log to indicate what transactions have been replicated and which have not. This information can be used by DM.
Global Transaction IDs (GTIDs) are used by recent MySQL versions' binary log to indicate what transactions have been replicated and which have not. This information can be used by DM.


## H

### HTAP

Hybrid Transactional Analytical Process (HTAP) is a database feature that allows both OLTP and OLAP workloads on the same database. For TiDB the HTAP feature is provided by using both TiKV for row storage and TiFlash for columnar storage. See [the definition of HTAP on the Gartner website](https://www.gartner.com/en/information-technology/glossary/htap-enabling-memory-computing-technologies) for more information.

## I

### IMDS

Instance Metadata Service (IMDS) is a AWS service that can be used to manage EC2 instances. See [Instance metadata](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-metadata.html) for more information.

### Index Merge

Index Merge is a method introduced in TiDB v4.0 to access tables. Using this method, the TiDB optimizer can use multiple indexes per table and merge the results returned by each index. In some scenarios, this method makes the query more efficient by avoiding full table scans. Since v5.4, Index Merge has become a GA feature.
Expand All @@ -64,8 +130,26 @@

The in-memory pessimistic lock is a new feature introduced in TiDB v6.0.0. When this feature is enabled, pessimistic locks are usually stored in the memory of the Region leader only, and are not persisted to disk or replicated through Raft to other replicas. This feature can greatly reduce the overhead of acquiring pessimistic locks and improve the throughput of pessimistic transactions.

## K

### KMS

Key Management Service (KMS) allows the storage and retrieval of secret keys in a secure way. Examples of this are the AWS KMS, GCP KMS and HashiCorp Vault. Various TiDB components can use this to manage the keys that are used for storage encryption and related services.

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[Vale.Avoid] Avoid using 'GCP'.

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{"message": "[Vale.Avoid] Avoid using 'GCP'.", "location": {"path": "glossary.md", "range": {"start": {"line": 137, "column": 129}}}, "severity": "ERROR"}
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Consider adding a sentence about how KMS is used in TiDB, e.g. "TiDB uses KMS to manage encryption keys for data at rest."

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Key Management Service (KMS) allows the storage and retrieval of secret keys in a secure way. Examples of this are the AWS KMS, GCP KMS and HashiCorp Vault. Various TiDB components can use this to manage the keys that are used for storage encryption and related services.
Key Management Service (KMS) allows the storage and retrieval of secret keys in a secure way. Examples of this are the AWS KMS, GCP KMS and HashiCorp Vault. TiDB uses KMS to manage encryption keys for data at rest.

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The sentence is missing an article before 'storage encryption'.

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Key Management Service (KMS) allows the storage and retrieval of secret keys in a secure way. Examples of this are the AWS KMS, GCP KMS and HashiCorp Vault. Various TiDB components can use this to manage the keys that are used for storage encryption and related services.
Key Management Service (KMS) allows the storage and retrieval of secret keys in a secure way. Examples of this are the AWS KMS, GCP KMS, and HashiCorp Vault. Various TiDB components can use this to manage the keys that are used for storage encryption and related services.


### KV

Key-Value (KV) is a way storing information that allows easy store and retrieval by specifying the key. Multiple values can be stored under a single key by encoding them. TiKV is implementing this by TiDB mapping tables and indexes into Key-Value entries.
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The sentence is missing an article before 'storing information'.

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Key-Value (KV) is a way storing information that allows easy store and retrieval by specifying the key. Multiple values can be stored under a single key by encoding them. TiKV is implementing this by TiDB mapping tables and indexes into Key-Value entries.
Key-Value (KV) is a way of storing information that allows easy store and retrieval by specifying the key. Multiple values can be stored under a single key by encoding them. TiKV is implementing this by TiDB mapping tables and indexes into Key-Value entries.


## L

### LDAP

Lightweight Directory Access Protocol (LDAP) is a standardized way of accessing a directory with information. This is often used to store information on accounts. This is used in TiDB by [LDAP authentication plugins](/security-compatibility-with-mysql.md#authentication-plugin-status).
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The sentence is missing an article before 'accessing a directory'.

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Lightweight Directory Access Protocol (LDAP) is a standardized way of accessing a directory with information. This is often used to store information on accounts. This is used in TiDB by [LDAP authentication plugins](/security-compatibility-with-mysql.md#authentication-plugin-status).
Lightweight Directory Access Protocol (LDAP) is a standardized way of accessing a directory with information. This is often used to store information on accounts. This is used in TiDB by [LDAP authentication plugins](/security-compatibility-with-mysql.md#authentication-plugin-status).


### LTS

Long Term Support (LTS) are software versions that are well tested, production ready and are supported for a long term. See [TiDB Versioning](/releases/versioning.md) for more details.
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The sentence is missing an article before 'software versions'.

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Long Term Support (LTS) are software versions that are well tested, production ready and are supported for a long term. See [TiDB Versioning](/releases/versioning.md) for more details.
Long Term Support (LTS) are software versions that are well tested, production ready, and are supported for a long term. See [TiDB Versioning](/releases/versioning.md) for more details.


### leader/follower/learner

Leader/Follower/Learner each corresponds to a role in a Raft group of [peers](#regionpeerraft-group). The leader services all client requests and replicates data to the followers. If the group leader fails, one of the followers will be elected as the new leader. Learners are non-voting followers that only serves in the process of replica addition.
Expand All @@ -82,10 +166,22 @@

## O

### OLAP

OnLine Analytical Processing (OLAP) are describing database workloads that mostly deal with analytical workloads like reporting. The characteristics of this is read heavy queries that process many rows.

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[PingCAP.Ambiguous] Consider using a clearer word than 'many' because it may cause confusion.

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{"message": "[PingCAP.Ambiguous] Consider using a clearer word than 'many' because it may cause confusion.", "location": {"path": "glossary.md", "range": {"start": {"line": 171, "column": 193}}}, "severity": "INFO"}
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⚠️ Potential issue

Fix grammar and style issues

Several grammar issues need to be addressed:

-OnLine Analytical Processing (OLAP) are describing database workloads that mostly deal with analytical workloads like reporting.
+Online Analytical Processing (OLAP) describes database workloads that mostly deal with analytical tasks like reporting.

-OnLine Transaction Processing (OLTP) are describing database workloads that mostly deal with transactional workloads
+Online Transaction Processing (OLTP) describes database workloads that mostly deal with transactional operations

-Out of Memory (OOM) is a situation where a system fails due to a a lack of available memory.
+Out of Memory (OOM) is a situation where a system fails due to a lack of available memory.

-Followers in pending cannot be elected as leader.
+Followers in pending state cannot be elected as the leader.

-Uniform Resource Identifier (URI) is a uniform way
+A Uniform Resource Identifier (URI) is a uniform way

-Universally Unique Identifier (UUID) is a 128-bit
+A Universally Unique Identifier (UUID) is a 128-bit

Also applies to: 179-179, 183-183, 216-216, 308-308, 312-312

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[uncategorized] ~171-~171: This verb does not appear to agree with the subject. Consider using a different form.
Context: ...AP OnLine Analytical Processing (OLAP) are describing database workloads that most...

(AI_EN_LECTOR_REPLACEMENT_VERB_AGREEMENT)

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[warning] 171-171:
[vale] reported by reviewdog 🐶
[PingCAP.Ambiguous] Consider using a clearer word than 'many' because it may cause confusion.

Raw Output:
{"message": "[PingCAP.Ambiguous] Consider using a clearer word than 'many' because it may cause confusion.", "location": {"path": "glossary.md", "range": {"start": {"line": 171, "column": 193}}}, "severity": "INFO"}

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Consider rephrasing this definition to be more descriptive of what OLAP workloads are in the context of TiDB. For example, "OnLine Analytical Processing (OLAP) refers to database workloads that primarily involve complex analytical queries, such as reporting and data warehousing, often characterized by read-heavy operations and large data scans."

Style Guide References

Suggested change
OnLine Analytical Processing (OLAP) are describing database workloads that mostly deal with analytical workloads like reporting. The characteristics of this is read heavy queries that process many rows.
OnLine Analytical Processing (OLAP) refers to database workloads that primarily involve complex analytical queries, such as reporting and data warehousing, often characterized by read-heavy operations and large data scans.

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The sentence is not clear enough. It is recommended to clarify the characteristics of OLAP workloads and improve readability.

Suggested change
OnLine Analytical Processing (OLAP) are describing database workloads that mostly deal with analytical workloads like reporting. The characteristics of this is read heavy queries that process many rows.
OnLine Analytical Processing (OLAP) describes database workloads that primarily handle analytical tasks, such as reporting. These workloads are characterized by read-heavy queries that process a large number of rows.


### Old value

The "original value" in the incremental change log output by TiCDC. You can specify whether the incremental change log output by TiCDC contains the "original value".

### OLTP

OnLine Transaction Processing (OLTP) are describing database workloads that mostly deal with transactional workloads like selecting, inserting, updating and deleting small sets of records.
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The sentence is not clear enough. It is recommended to clarify the characteristics of OLTP workloads and improve readability.

Suggested change
OnLine Transaction Processing (OLTP) are describing database workloads that mostly deal with transactional workloads like selecting, inserting, updating and deleting small sets of records.
OnLine Transaction Processing (OLTP) describes database workloads that primarily handle transactional tasks, such as selecting, inserting, updating, and deleting small sets of records.


## OOM

Out of Memory (OOM) is a situation where a system fails due to a a lack of available memory. See [Troubleshoot TiDB OOM Issues](/troubleshoot-tidb-oom.md) for more details.
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There is a typo in the sentence. The word 'a' is repeated.

Suggested change
Out of Memory (OOM) is a situation where a system fails due to a a lack of available memory. See [Troubleshoot TiDB OOM Issues](/troubleshoot-tidb-oom.md) for more details.
Out of Memory (OOM) is a situation where a system fails due to a lack of available memory. See [Troubleshoot TiDB OOM Issues](/troubleshoot-tidb-oom.md) for more details.


### Operator

An operator is a collection of actions that applies to a Region for scheduling purposes. Operators perform scheduling tasks such as "migrate the leader of Region 2 to Store 5" and "migrate replicas of Region 2 to Store 1, 4, 5".
Expand All @@ -111,10 +207,18 @@

[Partitioning](/partitioned-table.md) refers to physically dividing a table into smaller table partitions, which can be done by partition methods such as RANGE, LIST, HASH, and KEY partitioning.

### PD

Placement Driver (PD) is an important component of the [TiDB Architecture](/tidb-architecture.md#placement-driver-pd-server) that is responsible to store metadata and run the [TSO](/tso.md) that hands out timestamps that are used for transactions. It also orchestrates the data placement on TiKV and runs the [TiDB Dashboard](/dashboard/dashboard-overview.md).
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The sentence is too long. Please split it into several sentences for better readability.

Suggested change
Placement Driver (PD) is an important component of the [TiDB Architecture](/tidb-architecture.md#placement-driver-pd-server) that is responsible to store metadata and run the [TSO](/tso.md) that hands out timestamps that are used for transactions. It also orchestrates the data placement on TiKV and runs the [TiDB Dashboard](/dashboard/dashboard-overview.md).
Placement Driver (PD) is an important component of the [TiDB Architecture](/tidb-architecture.md#placement-driver-pd-server). It is responsible for storing metadata and running the [TSO](/tso.md), which hands out timestamps used for transactions. PD also orchestrates data placement on TiKV and runs the [TiDB Dashboard](/dashboard/dashboard-overview.md).


### pending/down

"Pending" and "down" are two special states of a peer. Pending indicates that the Raft log of followers or learners is vastly different from that of leader. Followers in pending cannot be elected as leader. "Down" refers to a state that a peer ceases to respond to leader for a long time, which usually means the corresponding node is down or isolated from the network.

### PiTR

Point in Time Recovery (PiTR) is a database feature that allows the user to restore to a specific point in time (for example just before an accidental `DELETE` statement). See [TiDB Log Backup and PITR Architecture](/br/br-log-architecture.md) for more details.

### Point Get

Point get means reading a single row of data by a unique index or primary index, the returned resultset is up to one row.
Expand All @@ -125,6 +229,10 @@

## Q

### QPS

Queries Per Second (QPS) is a performance metric of a database service.
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The definition of QPS is too brief and lacks context. It is recommended to provide more details on its significance and how it is used in performance evaluation.

Suggested change
Queries Per Second (QPS) is a performance metric of a database service.
Queries Per Second (QPS) is a performance metric of a database service that measures the number of queries a database can handle in one second. It is an important indicator of the system's ability to process requests efficiently and is often used to evaluate the performance and scalability of database systems.


### Quota Limiter

Quota Limiter is an experimental feature introduced in TiDB v6.0.0. If the machine on which TiKV is deployed has limited resources, for example, with only 4v CPU and 16 G memory, and the foreground of TiKV processes too many read and write requests, the CPU resources used by the background are occupied to help process such requests, which affects the performance stability of TiKV. To avoid this situation, the [quota-related configuration items](/tikv-configuration-file.md#quota) can be set to limit the CPU resources to be used by the foreground.
Expand All @@ -135,6 +243,10 @@

Raft Engine is an embedded persistent storage engine with a log-structured design. It is built for TiKV to store multi-Raft logs. Since v5.4, TiDB supports using Raft Engine as the log storage engine. For details, see [Raft Engine](/tikv-configuration-file.md#raft-engine).

### RAG

Retrieval-Augmented Generation (RAG). See [Vector Search Overview](/vector-search-overview.md#use-cases) for more details.
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The abbreviation RAG is introduced without context. It is recommended to provide a brief explanation of what Retrieval-Augmented Generation (RAG) is before referring to the detailed documentation.

Suggested change
Retrieval-Augmented Generation (RAG). See [Vector Search Overview](/vector-search-overview.md#use-cases) for more details.
Retrieval-Augmented Generation (RAG) is a technique that combines retrieval-based methods with generative models to enhance information generation. See [Vector Search Overview](/vector-search-overview.md#use-cases) for more details.


### Region/peer/Raft group

Region is the minimal piece of data storage in TiKV, each representing a range of data (256 MiB by default). Each Region has three replicas by default. A replica of a Region is called a peer. Multiple peers of the same Region replicate data via the Raft consensus algorithm, so peers are also members of a Raft instance. TiKV uses Multi-Raft to manage data. That is, for each Region, there is a corresponding, isolated Raft group.
Expand All @@ -145,10 +257,18 @@

The mechanism of Region split is to use one initial Region to cover the entire key space, and generate new Regions through splitting existing ones every time the size of the Region or the number of keys has reached a threshold.

### restore
### Restore

Restore is the reverse of the backup operation. It is the process of bringing back the system to an earlier state by retrieving data from a prepared backup.

### RPC

Remote Procedure Call (RPC) is a way for software components to communicate. In a TiDB cluster gRPC standard is used for communication between different components such as TiDB, TiKV and TiFlash.
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low

Consider rephrasing this sentence to use active voice: "TiDB uses gRPC for communication between its components."1

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Suggested change
Remote Procedure Call (RPC) is a way for software components to communicate. In a TiDB cluster gRPC standard is used for communication between different components such as TiDB, TiKV and TiFlash.
Remote Procedure Call (RPC) is a way for software components to communicate. TiDB uses gRPC for communication between its components such as TiDB, TiKV and TiFlash.

Footnotes

  1. Use the active voice whenever possible. (link) ↩

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The sentence is missing a comma after 'cluster'.

Suggested change
Remote Procedure Call (RPC) is a way for software components to communicate. In a TiDB cluster gRPC standard is used for communication between different components such as TiDB, TiKV and TiFlash.
Remote Procedure Call (RPC) is a way for software components to communicate. In a TiDB cluster, gRPC standard is used for communication between different components such as TiDB, TiKV and TiFlash.


### RU

Request Unit (RU) is used in TiDB to describe the unit for the resource usage. This is used with [Resource Control](/tidb-resource-control.md) to manage resource usage.
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The sentence is missing a comma after 'usage'.

Suggested change
Request Unit (RU) is used in TiDB to describe the unit for the resource usage. This is used with [Resource Control](/tidb-resource-control.md) to manage resource usage.
Request Unit (RU) is used in TiDB to describe the unit for the resource usage. This is used with [Resource Control](/tidb-resource-control.md) to manage resource usage.


## S

### scheduler
Expand All @@ -160,6 +280,10 @@
- `hot-region-scheduler`: Balances the distribution of hot Regions
- `evict-leader-{store-id}`: Evicts all leaders of a node (often used for rolling upgrades)

### SST

Static Sorted Table, Sorted String Table or Sorted Sequence Table (SST) is the file storage format of RocksDB.
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Consider adding a brief explanation of what RocksDB is, e.g. "RocksDB is an embedded key-value store used by TiKV."

Suggested change
Static Sorted Table, Sorted String Table or Sorted Sequence Table (SST) is the file storage format of RocksDB.
Static Sorted Table, Sorted String Table or Sorted Sequence Table (SST) is the file storage format of RocksDB, an embedded key-value store used by TiKV.

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The definition of SST is unclear and lacks context. It is recommended to provide a more detailed explanation of what SST is and its role in RocksDB.

Suggested change
Static Sorted Table, Sorted String Table or Sorted Sequence Table (SST) is the file storage format of RocksDB.
Static Sorted Table, Sorted String Table, or Sorted Sequence Table (SST) is a file storage format used by RocksDB. It organizes data in a sorted manner to optimize read and write operations, enhancing the performance of the database.


### Store

A store refers to the storage node in the TiKV cluster (an instance of `tikv-server`). Each store has a corresponding TiKV instance.
Expand All @@ -170,6 +294,20 @@

Top SQL helps locate SQL queries that contribute to a high load of a TiDB or TiKV node in a specified time range. For details, see [Top SQL user document](/dashboard/top-sql.md).

### TPS

Transactions Per Second (TPS) is a performance metric of a database.
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Consider rephrasing this definition to be more descriptive of what TPS measures. For example, "Transactions Per Second (TPS) is a key performance indicator (KPI) that measures the number of transactions a database system can process per second."

Suggested change
Transactions Per Second (TPS) is a performance metric of a database.
Transactions Per Second (TPS) is a key performance indicator (KPI) that measures the number of transactions a database system can process per second.

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The definition of TPS is too brief and lacks context. Consider providing more details about its significance in database performance.

Suggested change
Transactions Per Second (TPS) is a performance metric of a database.
Transactions Per Second (TPS) is a performance metric of a database that measures the number of transactions a system can process in one second. It is a critical indicator of the system's throughput and efficiency.


### TSO

Because TiKV is a distributed storage system, it requires a global timing service, Timestamp Oracle (TSO), to assign a monotonically increasing timestamp. In TiKV, such a feature is provided by PD, and in Google [Spanner](http://static.googleusercontent.com/media/research.google.com/en//archive/spanner-osdi2012.pdf), this feature is provided by multiple atomic clocks and GPS. For details, see [TSO](/tso.md).

## U

### URI

Uniform Resource Identifier (URI) is a uniform way of describing a resource. See [Uniform Resource Identifier](https://en.wikipedia.org/wiki/Uniform_Resource_Identifier) on Wikipedia for more information.
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low

Consider rephrasing this definition to be more descriptive of what URI is. For example, "Uniform Resource Identifier (URI) is a string of characters that identifies a resource, enabling uniform identification of resources."

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Uniform Resource Identifier (URI) is a uniform way of describing a resource. See [Uniform Resource Identifier](https://en.wikipedia.org/wiki/Uniform_Resource_Identifier) on Wikipedia for more information.
Uniform Resource Identifier (URI) is a string of characters that identifies a resource, enabling uniform identification of resources.

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The explanation of URI could be expanded to provide more context about its use in TiDB.

Suggested change
Uniform Resource Identifier (URI) is a uniform way of describing a resource. See [Uniform Resource Identifier](https://en.wikipedia.org/wiki/Uniform_Resource_Identifier) on Wikipedia for more information.
Uniform Resource Identifier (URI) is a uniform way of describing a resource, which is used in TiDB to identify and access various resources within the system. See [Uniform Resource Identifier](https://en.wikipedia.org/wiki/Uniform_Resource_Identifier) on Wikipedia for more information.


### UUID

Universally Unique Identifier (UUID) is a 128-bit (16 byte) generated ID that can be used to identify records in a database. See [UUID](/best-practices/uuid.md) for more information on how UUID's are used in TiDB.
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The explanation of UUID should clarify its importance and usage in TiDB.

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Universally Unique Identifier (UUID) is a 128-bit (16 byte) generated ID that can be used to identify records in a database. See [UUID](/best-practices/uuid.md) for more information on how UUID's are used in TiDB.
Universally Unique Identifier (UUID) is a 128-bit (16 byte) generated ID that can be used to uniquely identify records in a database, ensuring data integrity and consistency. See [UUID](/best-practices/uuid.md) for more information on how UUID's are used in TiDB.

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