cheat - Cheat allows you to create and view interactive cheatsheets on the command-line.

grep - grep is a command-line utility for searching plain-text data sets for lines matching a regular...

cheat.sh - The only cheat sheet you need Unified access to the best community driven documentation

PowerGREP - Quickly search through large numbers of files on your PC or network using powerful text patterns to find exactly the information you want. Search and replace with plain text or regular expressions to maintain web sites, source code, reports, ...

explainshell - Match command-line arguments to their help.

dnGREP - dnGrep allows you to search across files with easy-to-read results.