# Backup Types

+ Backup types are categorized by how applications interact with data in the database during the backup operation:
  + **`Hot`** backups generally allows applications read and write access to the data
  + **`Cold`** backups generally does not allow applications to access data, which means the database is out-of-service
    + In `TiDB`, **`cold`** backup is not recommended
  + **`Warm`** backups allows applications read access and disallows the write access

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`Cold` backups are not recommended because: 
a) By using `cold` backups, you have to shut down the database management system for a long time;
b) On a distributed system it is hard to make sure that all components have been copied correctly by yourself.