Or consider a 64-bit game system like the Sony Playstation or Nintendo 64. Upgrades may seem unnecessarily complicated, but part of that perception is the way most people think about computers. Computers are generally considered as a single item, like a television set. It's really a collection of separate elements, more like a component stereo. You can buy better speakers without replacing your entire stereo, but you may find your new speakers stress your old amp.
Computer components are much the same.
You can upgrade just about everything in your machine. A new modem may give you faster Web browsing and downloads, as well as the ability to use your computer as a voice-mail system or fax machine. More memory will make everything run better. A new CPU may be an option. A bigger hard drive, faster CD ROM drives, CD recorders, DVD players, TV tuners, 3-D video accelerators, and even a whole new motherboard are also options.