Sloths are cousins, not of monkeys, but of anteaters and armadillos, and all three are found only in the New World.
Hanging upside down high in a tree, they reach out with sinuous arms to tear slowly but firmly at their favourite leaves.
Like cows and sheep, they have several stomachs where the long process of digesting all that greenery can take place. Even so, there is not much energy to be had from such a diet, so the sloth doesn't waste any. Their movements are preternaturally slow, of course, and they like nothing better than sunbathing, especially in the morning, to warm their tummies and help speed their digestion.
Amazingly, they are confident swimmers.
Once a week they clamber down to the forest floor, poke a hole in the earth, make a discrete deposit, and slowly make their way back up.
A howler monkey, whose diet is similar, would accomplish the equivalent task on the move, high in the trees (and will deliberately do so on your head if he doesn't like you). Why does the sloth go to all that bother?
The answer seems to be that the sloth is doing some gardening. It doesn't roam far, spending its life on perhaps 40 individual trees, but takes about 10% of their output of leaves - a huge proportion. Mineral nutrients are hard to come by in the forest so by returning a proportion (perhaps as much as half) accurately to the roots the next leaf crop is given a boost.
Yet another reason for admiring the sloth.