Linux under which, Whereis, locate, find command function

1 which    view the location of the executable file, or locate the command alias 2 whereis  View the location of the file 3 locate the   system database to find the file location, the database is updated approximately once a day 4 find     according to the search criteria, Search hard disk Query file name (find can also be based on file size-size time-atime Regular expression-regex)

When we can't find the files we need with Whereis and locate, we can use find, but find is traversing lookups on the hard disk, consumes hard disk resources, and is inefficient, so we recommend using Whereis and locate first.

Linux under which, Whereis, locate, find command function