Generally speaking, it's a generic warning lamp for many issues. First and foremost, read the owners manual for possible solutions. On some vehicles the lamp illuminates when a mileage plateau is reached at 30,000, 60,000, or 90,000 miles, as a warning for scheduled service due. It may also be for something as simple as a gas cap not tightened. You could go to Autozone and have the check light read for free. They do this in hopes of selling you the replacement part. Sometimes the warning lamp resets after 100 miles, then the system self checks and may or may not come back on. Last but not least, you can take the vehicle to your mechanic and have them diagnose and repair the vehicle as necessary.
Sometimes pulling the battery cable for 5 minutes will reset the check light. If it comes back then you know there is a problem that needs to be looked at. Don't forget to write down the radio presets before pulling the cable. The main thing is to not let a small problem become a big problem to where the vehicle is undrivable.