Lord Ganesha is the Supreme Brahma. He is not considered to be different from Shri Vishnu, Shri Shiva, Shakti and Brahma. But from the viewpoint of work and Leela, the Supreme Nirguna Nirakar Brahma manifests himself in different forms with different qualities. Lord Ganesha is considered to be the first to be worshipped. Among all the gods, only Ganapati Ji is entitled to be worshipped first. Lord Ganesha has had infinite incarnations in different times and universes, which cannot be described even in hundreds of years. But the main 8 incarnations of Lord Ganesha are considered to be Brahmadharaka which are briefly called Ashta Vinayaka. These incarnations are considered to have great importance in the spiritual field. All these incarnations express the qualities of Brahma in different forms. All these incarnations of Lord Ganesha destroyed the demons present in the form of various disorders. These incarnations have been described in detail in Mudgala Purana.