In some games, particularly those with an overworld map, players can take these items to a shop-like place and exchange them for new abilities or equipment.
Usually, such treasure items are found in small quantities as one progresses through a level, but by exploring, players can often find secret areas containing a large number of them.
In some platformers, particularly those with a hit counter such as the Kirby games, medicine, food or energy containers are found, which give the player extra health or defensive ability.
In some games, such as the Sonic series, the treasure items (rings) double as a method of enabling extra hits.
Often in adventure games there are many puzzles that need to be completed in order for the player to advance through the dungeons or levels.
In Minecraft, items range from weapons to tools to miscellaneous things like music discs or spawn eggs.
While no items are required for completion of puzzles or to access certain areas, they are mandatory for progression in the game and for defeating the bosses.
Sometimes, in games with large amounts of different weapons, there will also be specialized ammo packs, like napalm canisters or rockets/grenades for rocket and grenade launchers, respectively.
Generally, more powerful weapons (such as the aforementioned rocket launchers and flamethrowers) tend to be found later in the game.
In some games that cross genres, like Twisted Metal, the weapons come in the form of power-ups that have very limited duration.