No matter how well they are made, vehicles can still have design and/or manufacturing problems. When the government thinks the problem is REALLY serious, they require the manufacturer to issue a recall notice and fix the car free of charge. The manufacturer then tries to contact everyone who owns this type of vehicle. As you may have guessed, this is a very tough thing to do.
These recalls ALWAYS affect safety, so take them seriously! It is fairly simple to find out if your car has been recalled.
The government has links on its websites, such as http://www.nhtsa.gov, and there are many other websites with free recall information and searches. These sites include carfax.com, autobytel.com, and dmv.org.
Recalls are serious, but luckily, not very common. Sometimes there are less significant issues—issues that may not directly affect your safety—that are typically distributed through a Technical Service Bulletin, or TSB. A TSB tells service centers how to repair a frequent or difficult problem.
The pros get updated information through subscription plans; they are also available in consumer versions for a reasonable cost.
So if your vehicle has a recall, get the work done and keep yourself safe!