Human being

1. Central Processing Unit, RAM, and Hard Disk Drive
2. Integrated Sensors of Medium Wave Electromagnetic Radiation for 3D imaging
3. Verbal I/O Stream
4. Sensor of Chemical Substances
5. Power Supply: accepts both solid and liquid fuel, as well as a gas composed of mainly nitrogen and oxygen
6. 2 × Alimentary Port (female units only)
7. ELO/CPC [Excess Liquid Output/Child Process Constructor] (front panel),
USB Port [Universal Shitting Breach] ⁽⁷ (back panel)
8. External Memory Device ⁽⁸
9. Floppy Disk and an External Saving Device ⁽⁹
10. Touchpad

The units come in many colours and shapes, but unfortunately clip-on skins are not available. If you want to change the appearance of your unit, you have to undergo a series of surgical operations, which sometimes can damage the unit. Not all units are compatible with each other, but in some cases you can change your behaviour modes to compensate differences of operating systems. Otherwise reprogramming of the unit is quite difficult. In general, backward compatibility is quite usual, but you can also update your operating system (though this has to be done manually, there are no automated update programs).

Footnotes:
7. The USB Port is a security risk, because hackers use it as a backdoor
8. The hand is that of Brittany Murphy in the film Don't Say a Word
9. In case you can't figure it out, there is a paper and a pencil in the image