The GameCube's power supply is internal. The whole system is very easy to transport.
An internal power supply is usually a battery. An external power supply means the electric current that you get by plugging your device into a wall outlet. If you do not have to plug it in, then it has its own power supply inside the actual device, in other words, it is internal. Aside from a battery, it could have photovoltaic cells to generate power, or other internal sources of power, anything other than an external source.
All computers have an internal power supply... An external one is simply for back up if you lose power.
A power supply that is designed to be outside the case of the computer. Most laptop computers use an external power supply rather than an internal one to reduce size and weight while the laptop runs on battery power.
That is a device that is inside the computer. An internal hard drive, for instance, is physically mounted inside the computer. It is not made to be used outside the computer, though there are kits to convert internal hard drives into external drives. There are external storage devices that are made to plug into a USB port. External devices either require their own power supply, or they get power from a USB socket. Internal devices get their power from the power supply which is already in the computer.
Medical grade power supplies have additional components to isolate line voltage from internal voltage. Usually a 1 to 1 transformer with current and voltage cutoffs are used to transfer the energy from the mains to the internal circuits of the power supply. there are also additional opto isolators on the power supply that keep the external power from having any wired path to the internal side of the power supply.
More parts, like a case, indicators and a power supply.
That is a device that is inside the computer. An internal hard drive, for instance, is physically mounted inside the computer. It is not made to be used outside the computer, though there are kits to convert internal hard drives into external drives. There are external storage devices that are made to plug into a USB port. External devices either require their own power supply, or they get power from a USB socket. Internal devices get their power from the power supply which is already in the computer.
As compared to an internal floppy drive? You have to include a case, power supply and USB software in order to make them work.
A computer's power supply unit provides all needed voltages for the components of a computer that are internal. Externals either draw power from the USB bus (which in turn gets it's power from the aforementioned PSU or a Hub with a power supply) OR have their own internal power supply with a cable.
An internal modem consists of a card that is installed in the computer, it has no additional wires or hardware. An external modem is more expensive to produce because, in addition to the card, there is the plastic housing that contains it, indicator lights, and cables to connect it to your computer.
A steam engine is an external combustion engine.
We use the 250 ohms with the power supply because the internal resistance of a DC power supply is insufficient to develop a resistance.