Other forms: zeds
In Britain, the last letter of the alphabet is known as zed. If your name is Lizzie, you spell it with two zeds.
If you're from England, Canada, or New Zealand, the alphabet ends with zed, while in the U.S. it's pronounced zee. In most of the English-speaking world, comprehending a subject completely means understanding it from A to zed. Zed, from the Greek zēta, was originally one of many words for Z, which included izzard, uzzard, and zod. Americans may have chosen to use zee in the 1600s as a way of differentiating themselves from the British.