Unfortunately, it means that someone has made an offer on the property and the seller has accepted. Typically contingent on a home inspection to the buyers satisfaction and financing. There could also be a home sale contingency which means the seller has an escape clause typically if another buyer comes along.
If this is a home you have already seen, you should consider putting a back up offer on the property if you are interested. Should the deal fall apart, you would be the next buyer with a contract on the property.
In my market (which is in Ohio) we show homes for backup when they are in contract. Deals do falls through and you can be there to pick up the pieces if it does.
If you are interested, I would recommend looking at the place with your buyer agent and placing your offer as backup.