Linux System Info commands

arch	show architecture of machine(1)
uname -m	show architecture of machine(2)
uname -r	show used kernel version
dmidecode -q	show hardware system components - (SMBIOS / DMI)
hdparm -i /dev/hda	displays the characteristics of a hard-disk
hdparm -tT /dev/sda	perform test reading on a hard-disk
cat /proc/cpuinfo	show information CPU info
cat /proc/interrupts	show interrupts
cat /proc/meminfo	verify memory use
cat /proc/swaps	show file(s) swap
cat /proc/version	show version of the kernel
cat /proc/net/dev	show network adpters and statistics
cat /proc/mounts	show mounted file system(s)
lspci -tv	display PCI devices
lsusb -tv	show USB devices
date	show system date
cal 2007	show the timetable of 2007
date 041217002007.00	set date and time - MonthDayhoursMinutesYear.Seconds
clock -w	save date changes on BIOS