There are several different types of puzzle to be found in IF, below is a list of many of them. Most, if not all of the puzzles can be categorised as one of these types, possibly more than one. Veteran IF fans may also be able to come up with more.

• Information, or clue, puzzles require that some piece of information is known. Typical examples are finding passwords or telephone numbers. Ideally this may not be used until it has been discovered 'in-game' so as to stop a player from using knowledge that the PC does not yet have.
• External knowledge puzzles rely on the player using information not discovered 'in-game'. This is generally used only as a copy protection method, with the required knowledge resting in the packaging. It can sometimes be difficult to judge when something is what the average player should know, and whet it is specialised knowledge.
• Map-making puzzles attempt to confuse and disorientate the player with similar (or even identical locations). There are two types of maze: those that can be easily drawn, and relate direction wise, and those that are based on some sort of logic, but do not match up with a simple map. Generally, if the description mentions the word 'twisty' or something similar, it's probably the latter.
• Experimentation puzzles present the player with some sort of puzzle that can only be solved through trial and error. Devices, controls or magic potion ingredients are all staples of this type of puzzle.
• Time/Geography puzzles rely on the PC being in the right place, at the right time (generally a set number of moves). Variants may require an object to be in the right place, or a task to be performed in time.
• Physical Modelling puzzles are those which require the player to have a good mental image of the situation to understand the solution. Sometimes the puzzle may also be solved simply be trial and error.
• Object/Inventory management puzzles, involve either tight gaps that you cannot squeeze through with large (sometimes not any) objects in your possession, or making tough choices about what to take. Having a limit on the PC's inventory is a form of permanent inventory management puzzle.
• Object puzzles require the PC to be carrying an object, use an object or put an object in the correct place.
• Arbitrary puzzles require the PC to do something nonsensical or for no apparent reason. These are normally mentioned in clues either 'in-game' or in the packaging it came in.
• Completely arbitrary puzzles involve doing something for no apparent reason, not even one mentioned in the game or packaging. These are normally there only for extra points on the score, and should not be necessary to progress.
• Verb selection puzzles are usually something to avoid. This may be another puzzle (or possibly just a very simple action that needs doing), but the exact phrasing of the command needs to be correct.
• Often this arises simply from poor parsers within the IF itself, or lack of forethought on the part of the writer.
• Tedious puzzles are those which fall into another category, but take so long, or so much effort on the part of the player that they really rather wish it wasn't there at all.
• Codes and Riddles are puzzles that involve the player solving a code, riddle or some other logical problem. They are not really solved 'in-game', though clues 'in-game' or in the packaging may be provided.

Some of the puzzles that you will come across will be integral parts of the plot, written in when the idea first germinated in the head of the writer. Indeed, it may originally have been a particularly fiendish puzzle that sparked off the whole idea of the plot. Most of the puzzles will have arrived out of a need to either give the player something to do, or to alter the tempo that the piece moves at. After all, an IF without puzzles is not much of an adventure.

The most important reason for the existence of puzzles in a game is to force the reader to experience the scenes. It would be a waste of all that careful planning if the reader could go from the start to the finish directly, without experiencing any emotional development and character interaction!

Puzzles may also be there to make the player stay in one place to observe other happenings at that location. Despite all this, puzzles are not, the reason for IF. A text adventure can exist without a plot, it would be fairly dull if you don't like doing Mensa problems, but it would be a text adventure, none the less. An IF without a plot is not much of a story. For this reason, ideally all of the puzzles should be there for a reason, no matter how small, but not just for the sake of it.

Other entries in this Project

• An Overview
• A Brief History
• Early Text Adventures
• Styles and Genres
• Plots
• The Player Character
• Other Characters
• Writing an IF
• Memories and Comments
• Links to other Websites