The next time you're in a crowded place, notice all the different types of walks that people have. Some people waddle, others saunter, and some drag their feet. It's amazing how almost everyone you see has their own unique walk. You've probably noticed the distinct way in which Mae West, Groucho Marx, John Wayne, and Charlie Chaplin all walk. If you want to peg a character, figure out how they walk.
Computer animators have a number of tools available for animating walks.
It seems as though software vendors have focused a considerable amount of effort on technology for animation walks, and quite a few new and innovative tools are available for automating all or part of the walking process. These sophisticated tools can be both a help and a hinderance. As the animator, you should still understand exactly how characters walk and how you want your characters to do it. If a piece of software helps you to get this done in half the time, that's fantastic. Just be sure that you, not a piece of software, are controlling the animation process.