The following article was originally published at 1UP.com, and is reprinted with permission.

Interactive Fiction: An Introduction

If you've ever wandered around Raccoon City looking for a gem to place into a slot, or if you've ever felt the rush of satisfaction upon solving one of Zelda's intricate systems of levers and objects, or if you were impressed by Knights of the Old Republic's clever NPCs and dialogue, then you owe a debt to interactive fiction. In a time when video games were much simpler and graphics cards were rare, interactive fiction (also known as text adventures) was the state of the art. This influential genre was the forerunner to virtually all of today's adventure games.

The basic components of interactive fiction (henceforth called IF) are a text parser that understands English commands and a convincing environment model that responds to those commands. Put more simply, IF lets the player tell the game what to do, and the game does different things in response. This isn't so far removed from modern adventure games; for example, instead of selecting Solid Snake's gas mask from the items menu, a player would type, "wear gas mask."

It's this style of gameplay that earned Zork and Hitchhiker's Guide to the Galaxy widely sung praises in the 70s and 80s, but what has IF done for us lately? That's where our guide to modern IF comes in. Here, we'll go into a brief history of how IF began, what it is, and how to play it. Next, we'll look at some modern games and their creators in depth, then finally finish off with a few hints for making your own. So grab your graph paper, and let's get started!

The (Abridged) History of I.F.

Graphical processing power on home PCs was not always as easy to come by as it is today. Rather than build a game with a few crude, hardware-specific images, the text-based IF game was born. The first ever created, Advent, was based on real-life Kentucky caves mapped out by Will Crowther and his wife. In order to convey the experience of spelunking to his children and to those who could no longer explore the now-closed-off caves, Will reproduced his maps in textual form, describing the caverns and passageways as he had found them.

Advent inspired lots of imitators, the most significant of which was Zork. Infocom, the best-known and most successful IF company, was founded on Zork's success. Most of the lasting IF classics came from this prolific company. Some of their most lasting games include Trinity, a cross-time adventure about nuclear weapons by Brian Moriarity, and A Mind Forever Voyaging by Steve Meretzky, a utopian simulation where you play as a sentient machine. The Lurking Horror, a nightmarish, Lovecraftian adventure set in the catacombs beneath M.I.T., is the direct precursor of today's survival horror. Douglas Adams, author of The Hitchhiker's Guide to the Galaxy, cowrote the IF adaptation of his own work with Meretzky.

Though Infocom was the most successful company producing IF, they were not the only one; other notables include Adventure House, founded by Scott Adams, and Sierra On-Line, cofounded by Roberta Williams. Williams was the first to add images to interactive fiction in Mystery House; though the game still used a text parser, it was the first real technological leap in the format since Advent, and a step down the road to graphical adventure games such as LucasArts' SCUMM titles. The format eventually gained enough notoriety to attract mainstream authors like Michael Crichton, James Clavell and Thomas M. Ditch, as well as former U.S. poet laureate Arthur Pinsky.

However, as home computing power grew and graphical power increased, the popularity of IF waned. Activision bought out Infocom, and though the company still produced original games for a period, IF was no longer popular enough to support them financially. The format might have died there, if it weren't so easy to replicate; in 1992, Graham Nelson (from whose much more comprehensive history this abridged version is adapted) released the Inform programming language. Now, using these tools, players could write Infocom-style IF without starting each game from scratch.

A homemade IF community began to form on USENET, and the first annual IF Competition was held in 1995. Since then, the number of entrants into the competition has increased every year. More and more IF continues to come out, breaking new and innovative ground each year. In many ways, things are better now for IF than they ever have been before. On the next page, we'll give you a crash course in how to play IF and take advantage of the boom of modern titles.