Caches can be grouped in three categories – with and without a paper log, and events. A BIT Cache is a laminated card with a QR code, similar to Munzee.
According to Dave Ulmer's message, this cache was a black plastic bucket that was partially buried and contained software, videos, books, food, money, and a slingshot. The activity was originally referred to as GPS stash hunt or gpsstashing.Larger containers such as plastic storage containers (Tupperware or similar) or ammunition boxes can also contain items for trading, such as toys or trinkets, usually of more sentimental worth than financial.Geocaching was originally similar to the 160-year-old game letterboxing, which uses clues and references to landmarks embedded in stories.Container sizes range from "nanos", particularly magnetic nanos, which can be smaller than the tip of finger and have only enough room to store the log sheet, to 20-liter (5 gallon) buckets or even larger containers, such as entire trucks.The most common cache containers in rural areas are lunch-box-sized plastic storage containers or surplus military ammunition cans.Geocaches may also be complex, involving lengthy searches, significant travel, or use of specialist equipment such as SCUBA diving, kayaking, or abseiling.
Different geocaching websites list different variations per their own policies.
Although not required, many geocachers decide to leave behind signature items, such as personal Geocoins, pins, or craft items, to mark their presence at the cache location.
Cachers who initially place a Travel Bug or Geocoins often assign specific goals for their trackable items.
Geocachers are free to take objects (except the logbook, pencil, or stamp) from the cache in exchange for leaving something of similar or higher value.
Aside from the logbook, common cache contents are unusual coins or currency, small toys, ornamental buttons, CDs, or books.
For the traditional geocache, a geocacher will place a waterproof container containing a log book (with pen or pencil) and trade items or trackables, then record the cache's coordinates.