Backside of the PC

PC Power Supply C14
Mouse and Keyboard PS2 keyboard (purple)
 
 
 
 
mouse (green)
USB Universal Serial Bus
Monitor VGA Video Graphics Array
Local Area Network LAN 8P8C Ethernet network connections, often called RJ45
Audio TRS 3.5 mm (stereo) Headphone Output (green)
 
 
 
Line Input (blue)
 
 
 
Microphone Input (pink)