foam yoga blocks

What is the point of yoga blocks? Worth the price?
Ok, so I'm eager to start yoga for toning, I heard videos, but adding blocks is good .. I went to Target to buy today and its like 11bucks a piece and you need 2 .. Can anyone tell me why its better or what I mean its a piece of foam 11bucks!?
When you perform certain poses if you are not flexible enough to reach all the way to the floor, you can use a block or two to help. This is to avoid exceeding a muscle or tendon – if it is too difficult to reach the earth, you do not want to force, if a block can help you land look a little closer! So it depends on you and your body if you block or not. Some do not use at all, while others can not do yoga without them. Incidentally, it is now essential that are part of the special foam. They are very light and easy to move, which explains why they are used. However, you can try something like a foot or a sturdy box, For example, if you do not want to spend $ 11 on some moss. Just make sure that whatever use or not Slide Away collapse because it could cause serious damage!
cork yoga blocks