Useful Linux Commands

Files / Filesystems

 * fuser - show which processes are using a specified file, file system, or socket
 * lsof - list of all open files and the processes that opened them

Hardware

 * lshw - detailed information on the hardware configuration of the machine

Operating System, Version, Kernel

 * lsb_release -a
 * cat /etc/issue
 * uname -a