- find - Versatile tool for searching for files based on name, size, date, etc.
- locate - Lists all files with a given word in the name
- whereis - Finds commands, source, and manpages
- which - Finds commands on the path
- grep - Searches for text/patterns within a file
- cksum - Calculate the checksum of a file.
- diff - Find differences between two files.
- file - Determine file type.
- ls - List the contents of a directory.
- lsattr - List the attributes of a file.
- md5sum - Calculate or check the MD5 checksum of a file
- wc - Displays line, word and character count for specified filename.
- cp - Copy a file from one location to another.
- dd - Copies a file and performs various conversions at the same time.
- some dd examples - This is good stuff. Must read for anyone serious about Linux
- du - Shows disk usage of files
- install - Copy file(s), preserving permissions.
- ln - Create a link to a file.
- mv - Rename or move a file.
- rename - Another renaming tool
- rm - Remove (delete) a file.
File Attribute Manipulation
- chgrp - Change the group ownership of a file or directory.
- chmod - Change the mode (access permissions) of a file or directory.
- chown - Change the ownership of a file or directory.
- getfacl - View the acl permissions associated with the file or directory.
- setfacl - Change the acl permissions associated with the file or directory.
- touch - Update access times or, potentially, create a file.