Computer utilities are kind of like the odd gadgets my wife has in a drawer in our kitchen. She's a fabulous cook, and certainly makes a lot of use of the standard kitchen items: bowls, mixing spoons, measuring cups. But every once in a while, I'll see her digging through a special drawer for a few moments, and then she'll pull out some contraption that looks more useless than useful. And then, suddenly, that wonderful, mysterious device performs some absolutely vital function that she needed done, and that no other device could have done so well—peeling potatoes a certain way, or slicing garlic just so, or extracting the last drops of juice out of a lemon. With a satisfied smile, she rinses it off, and back it goes into the magical drawer, to be reused at some odd juncture sometime in the future.
Computer utilities are a lot like this. Most computer users have a collection of rarely-used, but absolutely essential, programs on their machines, to be pulled out at odd times to do a specific task. These are not the programs we use every day for hours at a time, like word processors or Web browsers or email. No, these are more specialized applications.