In detail, there are more than 100 types of clouds, most of which being variations of other major types of clouds. For now, we'll stick to a few of the most basic ones.
One of the most common types of clouds that you see is the cumulus cloud. This cloud floats near to the earth's surface and is usually the cause of something like shade on a sunny day.
One of the other main types of clouds is the nimbostratus cloud. This type of cloud is the main culprit of light rainstorms and can easily be identified as very dark clouds.
The cumulonimbus cloud is the largest type of cloud you will see and has several stages to its life. Lasting for hours or sometimes even days, these clouds can cause torrential downpour, as well as high winds and turbulent weather and lighting. In the piloting community, these clouds pose the greatest threat to their safety due to the extreme conditions found within them.
The last basic type of cloud is the cirrus cloud. Being the highest up, these are commonly reffered to as wispy clouds, often being at the height that international airliners fly at. No need to worry though, these clouds almost never cause any threat to pilots or people on the ground for that matter, and are pretty awesome to look at!