Use Grep for Fast Search from the Command Line by Bonnie Eisenman

• Search the contents of files using grep
• Search directory contents recursively using grep
• Use find to search for filename patterns
• Search matching files by combining find and grep with xargs
• Search the contents of a git repository with git grep
• Show context around matches using grep
• Search for basic patterns using grep
• Use grep's extended regular expressions to find complex patterns
• Search for optional patterns with grep OR
• Specify line beginning and end in patterns using grep
• Match classes of characters using bracket expressions with grep
• Search with groups using grep
• Find matches excluding a pattern with grep