Re: Ooooh, it\'s dumb question time!
There are many different types of retirement plans, and you have to look at each one specifically.
There are a couple of things to keep in mind, though. Plans like a 401k plan are typically *owned* by the employee after they have become fully vested (the amount of time to become vested will vary with the plan. Might be relatively short like a couple of years, or much longer). The 401k is a retirement account, run separately from the company that you work for, that your employer has agreed to help set up and manage in some way. Often you are putting part of your salary (pre-taxes!) into the 401k to fund it. Typically the money in that account becomes yours, and you can take it with you if you change jobs. The really good plans will have the company matching some of your contributions. If you have a company-matching funds plan you'd better be putting in at least as much as they'll match - that's free money folks, step right up!
Other retirement packages (like pension plans) can be completely owned and operated by the company you work for. Receiving those benefits is much more dependent upon the contract that you are working under. Some of those plans can go away if the company folds, too.
The Roth IRA is also a great retirement plan that you can (and should) do on your own. In the Roth you buy into a plan (often invested in mutual funds or something similar) with your personal money (i.e. after taxes have been taken out), then the account grows, tax-free! Do the math kids, 'cause investing money that will grow tax free is a great investment. Start now. Now, I said. As soon as you have paid your rent and grocery money, put a little bit into a Roth IRA. You'll call me up and thank me in thirty years. Don't spend it on a new car that will lose all its value in 5 years. Have you ever seen the math on compound interest? That multiplication looks even better when you can take those proceeds out without having to pay 35% or 50% in taxes on it. Want to be a multi-millionaire when you retire?
[disclaimer] I have absolutely no financial background. There are probably errors in the descriptions above. Go and talk to a professional, educate yourselves and plan ahead.[/disclaimer]