A cartridge means an object that adds different functions or content to an electronic device (like a video game cartridge), or that refills something the device needs (like an ink cartridge for a printer).
Video game cartridges are quite simple to use. You simply slide it into the console and it usually displays a video game that you can now play from that cartridge.
A cartridge is easy to use. For example, an ink cartridge is easier to use than a bottle of ink. This is because all the ink is inside the cartridge.
A cassette is a small cartridge. The words have similar meanings.
