Traditional geocache hunts are such that the coordinates will take you directly to the cache. They will contain a container and a logbook at bare minium and may also include some tradable or trackable items. The main rule to remember is: if you take something, you must leave something of a similar or higher value. Some caches are themed, so be sure to read the rules before heading out. These are the typical hunts, and are often what beginners start with.
A multi-cache hunt requires going to two or more hunt locations to find the actual cache. Each intermediate cache holds the coordinates to the next cache site. There are also variations on this theme, called offset cache hunts, where each intermediate cache holds hints to find the next cache. These hints may point you to a monument, where the date on the monument is the hint to the final cache.
One form of a multi-cache hunt is a Wherigo cache. Instead of holding a clue or the coordinates to the next site, the container holds a Wherigo cartridge. This cartridge use the GPS coordinates to trigger events such as location based puzzles or stories. Currently these cartridges will only play on select Garmin handheld devices and GPS-enabled Pocket PCs.
This type of hunt requires you to solve a puzzle or riddle in order to uncover the coordinates to the cache. There are variations on this theme, such as giving false coordinates with hints to finding the real coordinates, or solving a puzzle to find a combination to a padlock. These puzzles may be rather easy or quite difficult.
This type of hunt combines letterboxing and geocaching in one hunt. The container will hold the traditional letterbox log book and rubberstamp. It may also hold treasures, but that is up to the cache creator. Traditional letterboxes are found using clues, whereas the hybrids are found using the GPS coordinates.
Earthcache is an educational based hunt. Each cache is located in an area where the hunter can learn about geology and how the environment affects the earth. These hunts are popular with educators. The Earthcache website() contains a section for uploading lesson plans and the ability to view general lesson plans.
As you can see, there is a geocache for every type of person – from the simple hike to a cache to indepth puzzles. The type of hunt you choose depends on your time available and what you are looking to get out of the experience.