# `TiDB` Files

__*TiDB file*__
__*zz-BGL*__

![`left`](./student-guide/diagram/IntroDuctionDatabaseFiles_aa_001_20220615.png)
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The binaries are the program to run `TiDB` server, `TiKV` server or `PD` server instances. 

The configuration file stores the cluster configuration of the node, which is loaded when the node starts. 

The log files are used to store the log entries for the node. 

Each node has `TiDB` binaries, configuration files and log files. 

The data files are stored on `TiKV` nodes for row-based data and `TiFlash` nodes for columnar data, while `Placement Driver (PD)` nodes store the KV's metadata.

In `TiKV`, log files refer to Write Ahead Log (WAL), and data files refer to MemTable and SST files.