What is the purpose of the file command in Linux?

The file command is used to determine the type of a file by analyzing its content and specific identifiers, and it will then output relevant information. Common uses include:

1. View the file type of a document: file filename
   For example, running “file test.txt” will output test.txt: ASCII text.
2. Batch viewing file types: file *
   This command will analyze the types of all files in the current directory and show the corresponding information.
3. Check the detailed information of the file by using the command “file -i filename”. This will display the type and encoding information of the file, for example, “test.txt: text/plain; charset=us-ascii”.

The command ‘file’ is quite commonly used in the Linux system to help users quickly determine the type of a file and choose the appropriate method of operation.