When i extend my joints they crack. as in i extend my arms and legs i hear a crack from the joint but i have no pain at all.

Normal if nonpainful: Joint cracking or popping is not an abnormality aslong as it is nonpainful. There are a variety of reasons why a joint can 'pop'. The most common reason is that there is a negative pressure inside your joint in relation to atmospheric pressure. Certain movements can create a acute reduction in the joint pressure in relation to joint volume and a 'pop' results.