A generic genre of game for the time, but still fun nonetheless.
There's a few different game modes to choose from. The main game pairs you off against several different Robotnik robots. The goal is to outlast the robot, in hopes that they're pile of beans reaches the top of their half of the screen first. Pulling off combos (either by connecting more than just 4 beans at once, or setting off a chain reaction of beans disappearing) drops extra beans on the other players side of the screen. This adds a nice element of strategy to the game. About half way through what could be loosely called the story mode, things get really fast past, and the robots get very good at pulling off combos of their own. Clearing all the stages can take a lot of time, but there is a password system available so you can pick up from where you left off.
There's also a practice mode where you play single player to hone your skills. You're only opponent here is yourself.
If endless practice isn't your thing, you can also go into puzzle mode. Here you have to figure out how to pull off specific tasks like clear X number of beans all at once.
It's not the most original game out there, but it still holds a lot of fun, and a respectable level of challenge that should keep you busy for a long time.