The Basics Skip this if you're a programmer. A computer programmer writes programs that run on computers. The actual work depends on the type of programmer. Maintenance programmers have to spend a lot of effort learning someone else's code in order to either fix it or make minor changes to it. Probably that code isn't well-enough documented or commented, so they have to figure it out the hard way.
Developers work on teams that build new systems.
They write new programs from scratch according to an overall design somebody handed to them, probably without explaining it very well. These days, most professional programmers spend most of their effort integrating systems written by other people with all of the systems already in place in their companies. That means they have to spend a lot of time becoming experts in both the new software and all of the existing systems, in order to design and build the necessary interfaces. The commercial system is probably very well-documented, which means the programmer has to figure out which page of which book contains the single piece of information needed right now. Robert Lewis works for Perot Systems Corporation as a consultant specializing in information systems effectiveness and the linkages between technology and business strategy.