They're for connecting things. Duh.
Cases, computers, monitors, routers, printers... basically anything that needs a little more cable action in its life.
Colours are for aesthetics, man. Orange is for the internet, green is for the network, and yellow is for the printer. Don't ask me why.
Want to see some USB Cable action?
Or perhaps Power Cords??
Then why are you even here? Go back to your cave.
Ask a Tech Support Specialist for help.
Cables. They're like, for cables.