Chrono Trigger is an absolute masterpiece that any self-respecting gamer should own in some form or another.
You are Crono (or whatever you named your character). You're getting excited for the Millenium Fair, which happens once every millenium, and your friend Lucca has invented something new called the Telepod (I think that's what it's called), and she wants you to see it. While you're at the fair, you meet someone named Marle, and you instantly befriend her. Then when Lucca is ready to show you her invention, she demonstrates its power by transporting you from one telepod to the other on the other side of the screen. Marle wants to give it a shot, but when she is being teleported, a pendant that you helped her find earlier shines and an opening in some time continuum sucks her in. You heroically take up the task of saving her from whatever she got herself into, and your quest begins.
The gameplay of Chrono Trigger is the same as most Final Fantasy games. The ATB (Active Time Battle) system, which utilizes a time bar per character to attack, is very well applied, making the battles feel realistic (for its time). The monsters all appear before battle on the map, and as such you can choose to battle or avoid them. But what's more, you and your enemies move around the screen, and what your attacks strength is ultimately changes with the difference from your enemies. Other than that, the combat works like a Final Fantasy game.
The game takes place in different time periods, and whatever happens in one time period ultimately changes whatever happens in future time periods. You travel using a machine called Epoch, and you can travel between a certain number of time periods, from prehistoric time to futuristic time. What is already a fairly large world is changed over time, and that is one of Chrono Trigger's best qualities.
Speakng of quality, the graphics are beautiful for 2D graphics. The art drecton of Chrono Trigger remains largely unmatched, and the musical score (courtesy of Nobou Uematsu) is perfectly applied to the on-screen action. The story is exquoisite, and it provides enough depth to be compelling, but not so much that you won't want to replay it.
In fact, the thing with Chrono Trigger is that it has a tremendous amount of replay value. Perfectly balanced in gameplay in terms of depth, lovely graphics and beautiful music ensure that the first time you play through Chrono Trigger will not be your last. But, actually, you'll want to play through the game more than once just to see all of its multiple endings.
That is where the innovation of this high quality masterpiece is: its pioneering of multiple endings. Sure, there were other games that did it, but none before- or perhaps even after- have done it quite as well as Chrono Trigger. There were at least a dozen endings, all of which were very interesting. It made that feature popular, and then came Resident Evil, which made them all the rage, but even that game just did not equal the insurmountable value you'll get from Chrono Trigger.
Chrono Trigger is one of the finest games ever released. If you don't have Chrono Trigger and have a SNES, then you absolutely must get it. If you have a Playstation/2/3, then you really should consider getting Final Fantasy Chronicles, or this version (if you're familiar with Japanese, that is). Either way, you're going to get a game that is very likely to change your life forever. It still holds up so well today that even today's games don't stack up to Chrono Trigger, for the most part. And that's a tell-tale sign of a classic, but calling Chrono Trigger a classic is just not doing it enough justice. It really is better than any other game of its kind. You owe it to yourself to play Chrono Trigger.