I call tabulation "bottom-up" because you start at the bottom (base cases) and work your way up to the top (your target problem). For Fibonacci, the "bottom" is fib(0) and fib(1), and the "top" is fib(n). You fill in the table from smallest to largest, so by the time you need fib(k), you've already computed all smaller values.
This is the opposite of top-down memoization, where you start at the target and recurse downward. Both approaches solve the same problems, just in opposite directions. Let me show you what bottom-up code looks like.