See recipe above. Also, fresh manure usually makes a compost pile hot. Choose hot compost if you do not mind adding manure, and if you are in a hurry. Worm compost is for the more relaxed Zen gardener. Compost is good for improving any garden soil.
Compost is nature-made dirt.
It has a fluffy consistency which is is good for root growth. It is full of nutrients that plants need to grow. Composting will help your garden. Gardeners usually do not put compost on top of established lawns because that would be like piling dirt on your lawn, but compost dug into the ground before you plant a lawn is a good idea. See next question.