Ancient Jewels Online is a type of fast-paced browser game in which you have to mix and match jewels of at least 3 in a group by swapping those which are next to each other. There are many variations of this arcade game, but each has certain elements which are common.
Usually the game's default mode is one which is governed by a time limit. The objective is to get the highest score possible by swapping and comboing jewels in the given time limit. Get high enough score and you will be taken to the next level, with each level having an unique shape and sets of differently colored jewels to mix and match by swapping. Difficulty increases as you progress, by having more colors on a given level, more difficult level shapes and higher scores to reach.
Some variations of this game may have a "puzzle mode", in which you have to completely clear pre-set levels with a fixed amounts of jewels present on the table.
The game can be played in quick bursts or for longer periods depending on your mood. Usually there are no restrictions on playtime and attainable levels.