copiado de http://www.dummies.com/how-to/content/linux-for-dummies-cheat-sheet.html
Common Linux Commands
Open-source Linux is a popular alternative to Microsoft Windows, and if you choose to use this low-cost or free operating system, you need to know some basic Linux commands to make your system smoothly. The most common Linux commands are shown in this table.
| Command | Description |
| cat [filename] | Display file’s contents to the standard output device (usually your monitor). |
| cd /directorypath | Change to directory. |
| cp [options] source destination | Copy files and directories. |
| date [options] | Display or set the system date and time. |
| grep [options] pattern [filesname] | Search files or output for a particular pattern. |
| ls [options] | List directory contents. |
| man [command] | Display the help information for the specified command. |
| mkdir [options] directory | Create a new directory. |
| mv [options] source destination | Rename or move file(s) or directories. |
| more [filename] | Display file’s contents page by page to the standard output device (usually your monitor). |
| passwd [name [password]] | Change the password |
| rm [options] directory | Remove (delete) file(s) and/or directories. |
| rmdir [options] directory | Delete empty directories. |
