Note: On Raspberry Pi models with built-in WiFi (e.g. the Raspberry Pi 3 model B), USB WiFi interfaces will use
wlan0is reserved for the first interface, in this case the internal one).
Since this is maybe the fourth time I've done this process on my Raspberry Pis, I decided to document the process of setting up cheap mini WiFi adapters on a Raspberry Pi A+/B+/2.
This process works great with any USB WiFi adapter that's supported out of the box. My three favorites (due to their inexpensive price and decent connection speed/reliability) are: