Zzt is a game from 1991, where you play by moving around on a map, shooting at various monsters and solving puzzles.

By itself it's not very special, however it has an in-game editor that allowed people to create their own levels, called "worlds" (using a programming language called ZZT-OP which substantially added flexibility). The simplicity of the game and editor, combined with the strict limitations (like its 60x25 entirely ascii interface) made creating a game a manageable feat even for teenagers.

The result? Thousands of varied worlds made by a dedicated community which remained active for more than a decade.

This is a very bare bones introduction, so here's a more detailed one (by somebody actually involved with zzt) including instructions on how to play zzt today, what games to play as a quick introduction and so on.

That aside, by today's standards, is zzt still worth checking out? Do the user-made games hold up?
Not really, IMO. Unless... you hold a special fascination for user produced content, with all the rawness, wackiness and creativity (or lack thereof) involved.

I'll be reviewing zzt games that I play. But first,

General considerations about zzt

As said above there are many different zzt games, however some flaws imo are inherent to zzt itself.

Now I'll address some things related to most zzt games I've played rather than zzt itself:

You can find the reviews here