20 Linux commands to manage your raspberry pi

1. Configuration settings
raspi-config

2. Staring UI/X11
startx

3. Know your CPU
cat /proc/cpuinfo

4. Show Memory Details 
cat /proc/meminfo

5. Show Partitions
cat /proc/partitions

6. Check Pi Version 
cat /proc/version

7. Show USB devices info:
lsusb

8. Shutdown device immediately:
sudo shutdown -r now

(you can also issue this command from ssh)

9. Search text in files
grep

10. Search files
find

11. Check system logs
dmesg

12. Check process, cpu usage etc.
top, ps

13. Check disks, usages etc.
df -h

14. Text editor for geeks
vi, nano

15. How long has the system has been running/up ?
uptime

16. History of user login success
last

17. Kill/stop a process
kill <process-id>

18. Memory stats
free -m

19. Show current date/time
date

20. Check network connection, IP address etc.
ifconfig