Using a Cell as a "Variable" in Formulas

So basically, say I wanted to do something with the range A:Z, for example do =SORT(A:Z, ...). Now, I have to change the range for the formulamultiple times in multiple locations, and it gets annoying when I have to manually enter everything over and over again. So, I was thinking to have a cell act like a variable of sorts. For example, a cell C10 would contain A:Z, and by passing =SORT(C10, ...) I could use C10 as a variable for A:Z.