Composting is a simple natural process, yet there are very complex biological and chemistry issues taking place behind the scenes in a compost pile to produce safe, healthy mature compost.
There are several ways to compost organic matter. You can compost by using a fancy compost bin, a compost pile, an earthworm bin, an aerated trash can, or just by sheet or trench composting by burying your "greens" and "browns" directly in your garden beds. Because there so many ways to compost these days, there is no excuse not to, whether you are a novice or an expert.
Cold composting refers to lazy, passive composting, or vermicomposting. You just pile organic matter in a pile and wait 6-12 months until its ready. Or you just feed earthworms to poop out the stuff in several months. No turning and no real physical labor. This is the classic, ancient way to do it.
Hot composting involves a balance of high nitrogen and high carbon materials, plus lots of constant aeration, in order to get beneficial aerobic bacteria and fungi growing inside the organic matter, in order to digest and break down these materials into mature compost, and ultimately humus. The waste product of heat energy is released from these aerobic microbes as they chemically break down the complex proteins and carbohydrates and other nutrients in this process. The heat energy is actually stored energy inside plant and animal wastes that got collected by the originally plants used or consumed by animals, way back when sunlight was captured by the plants from photosynthesis. (Pretty deep stuff huh?)
Hot composting is superior to cold composting because it guarantees no weed seed sprouting, no disease spreading to your garden, faster decomposition speed, and no stinky smells. You can make mature compost from a hot process in 1-2 months easily. Some experts can do in a few weeks!
Hope this helps you out a little bit.
Read all the books and websites you can on organic gardening and composting, until it starts making sense to you. Composting is like gourmet cooking, you get better at it and more creative with it, the more you do it.
Remember, composting happens with or without human intervention. As an organic gardener, all we do is speed up the natural process of decomposition, so we can get our gardens and lawns healthier faster.
Check out these articles I wrote, for more info on composting, organic gardening, and creative tea brewing: