Well, it depends on the contest, it can mean those things that they have just said, for example in "the rest of my life" (el resto de mi vida) or also can mean "descanso, reposo" as in "a rest is the best way to recover" (un descanso es la mejor forma de recuperarse).

lo demás restante el resto lo que sobra lo que queda lo que resta

You can say literally "el resto", if the rest are some things, you can say "el remanente" o "las sobras", but this depend from de situation. The literally traducción of "the rest" is "el resto" and is valid