Chest

Chests in Diablo games are objects in the game environment that the characters can interact with. This is generally not the same thing as a destructible object, as they also often contains items or gold.

Game Objects

Chests, barrels, dead bodies, and many other "clickable" type of objects are found throughout the dungeons and surface areas of Diablo III. These objects and containers function much as they did in the previous games in the series; once a player spots the object he or she points at it, and with a click the character proceeds to the object and opens it up. There are trapped objects in Diablo III, and the prizes found from said objects vary, much as they did in Diablo II.

Locked Chests

One that that appears to be changing in D3 is that we will not see the locked chests that were introduced in Diablo II. Bashiok explained why in a forum post on September 8, 2008:

There have been a few discussions about chests, what they meant in the previous game, and what they'll mean in Diablo III. Currently there are no locked chests, and it's not something we're looking to reintroduce for now. We have discussed varying chest quality and types, adding randomness not only to the appearance of a chest but also the value of items it may drop or possibly specifically what types of items it's guaranteed to drop. Mix it up a bit and make finding a chest exciting, but make finding a special chest something even rarer and more exciting. It could certainly make exploring the entire floor of a dungeon more compelling before moving on.

Players often complained about the locked chests in Diablo II, since they didn't necessarily drop any more or better stuff, and having to carry keys was thus a nuisance without much redeeming value. The D3 Team seems to be removing this argument before it can even begin.