grep

The grep command (global search for regular expression and print out) searches file(s) for a particular pattern of characters, and displays all lines that contain that pattern. It can be used with other commands like ps making it more useful.

It has the following syntax:

$ grep [options] pattern [files] e.g. $ grep "search-regex" file-1.txt

Visit the following resources to learn more:

• What is Grep? with examples
• Detailed Manual
• Linux Crash Course - The grep Command