The most predominant part of Hindu Religion is Lingam worship which is considered to be a representation of Hindu lord Shiva. Lingam worship is primarily found in temples. Lord Shiva has been considered to be the creator of this universe and is worshipped with great devotion almost everywhere. Devotees regard Lingam to be lord Shiva as he can exist in any form in nature like the very existence of fire which is detected by the presence of smoke.
In nature its presence can be felt. In most of the places Lingam is built manually but a rare occurrence can be seen at Amarnath, where melts and freezes thereby taking the form of Shiv Lingam. Devotees also arrange trips to visit Shiv Dhams which are Shiva temples where Lingam is worshipped.
From the old religious history it is apparent that god Shiva had been married to goddess Shakti and it is from their union that Lingam form has come into existence. It is a symbology of worshipping both of them.
Shiva lingams made of Quartz have no color of its own and take color of its surroundings. Thus it truly signifies the presence of Lord Shiva who is also devoid of form and characteristics. Further lingam worship helps attaining concentration of body and soul. Shiva lingam has three parts, of which the lower part represents Brahma, middle part Vishnu and the upper part Shiva itself. Thus Lingam worship is about worshipping all three lords together. Usually Shiva Lingam worship is prevalent in Chala or moveable and Achala or fixed form. Chala forms are worshipped at home and the other form is installed permanently to be worshipped at temples.