A pump is one of the basic things you must have for cycling. You generally have to pump up your tires every time you ride, so not having one is not an option! Fortunately there are many varieties on the market. Find a good one that’s on sale at your local bike shop, that feels good to you and is easy to operate. My preference for my 40-something eyes are the ones that have the gauge at the top of the pump, near the handle, rather than the bottom. MUCH easier to read!
There are basically two types of tire valves – Schrader and presta. Shrader valves are the same kind you have on your car tires. Basic, simple – you’ve used them for years. But presta valves are slightly different. Apparently they cope with the rigors of high-pressure tires much better, but they are a little tougher to use. First, you have to unscrew the top of the valve (you don’t really need a cap for this type) before you put any air in. Second, you need a special pump to fill them. Fortunately many pumps these days work on either Schrader or presta. (note, gas station pumps will typically only do Schrader) So, if you’ve got kids and/or a spouse who don’t ride high-performance bikes, then get a pump that adapts to both. (both of my pumps will automatically adapt to either valve type, and I don’t have to adjust a thing!)