On my quest, I've discovered that I have Raspberry Pi B+ with 512 MB RAM, which unfortunately doesn't have Wi-Fi built in. I do have an old Ativa Wireless USB Network Adapter, but it wasn't just plug-and-play.
I found a list of tested Wi-Fi Adapters,
https://elinux.org/RPi_USB_Wi-Fi_Adapters, but the Ativa AWGUA54 was not on the list.
A quick Google search and I've come across this:
...you can use USB adapters if they have Raspberry PI (Linux for ARM6) drivers.
And on another site:
This adapter is the same as the Belkin F5D7050 v4.
Back to the first list, the entry for the Belkin says "install firmware-ralink and add usbcore to /etc/modules; use
guide" and links to another site. A blogger explained the process of installing the drivers for the Raspberry Pi on
Raspberry Pi Wireless - Belkin 802.11g usb adapter Ralink RT2750W.