system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do computer chargers need those big adapters? Why can’t you just connect the devices to the power outlet with a cable?
gpt
The power coming out of the outlet is alternating current (AC). The power your computer uses is direct current (DC). Your laptop's power brick is converting AC to DC. It is also stepping down the voltage from 120V is something more suitable for charging your laptop's battery. Typically 12V to 20V.