There are countless versions of Snake and Ladders, including Chutes and Ladders. The point of the game was to travel from the beginning of the board to space 100 using dice. If you reached a space with a ladder you could climb to the space it's other end was on, if you reached a snake you would move back on the board to where it's head was. Wasn't is great reaching the longest ladder on the board? Or even strangely satisfying sliding down the longest or twirliest snake/chute?
I had a gigantic version that lay 3 feet by 3 feet on the ground and you could crawl around on it as you played with large puck-sized playing pieces while rolling a palm-sized die. We always played the version where you had to get the exact number to reach spot 100. If you were on 98, for example, you'd have to roll 2 to get to 100. If you rolled 3 you'd end up on space 99 -- forward 2 to 100, then back on to 99 to move 3.