Lord Ganesha is the most widely worshipped Hindu God. He is worshipped at the start of any action or venture, for he is considered to be the Lord who removes obstacles (vignam) and hence is also called Vigneshwara.

He has an elephant head, four arms. In his upper hands he holds the paasam (noose) and ankusam. The lower two hands are held in the abhaya and varada mudras. He is also seen holding his broken tusk in his right lower hand and a modhakam in his left lower hand. He has a huge belly and is fond of various sweets and fruits. He wears a snake as an ornament round his belly. He is depicted in seated, standing and dancing postures.

He is considered a bachelor, but according to another school of thought, he has two Sakthis - Siddhi & Buddhi. Siddhi represents success and prosperity. Buddhi represents wisdom. His vahana is a tiny mouse (mooshikam or minjur).

He is also known by other namavalis such as:

Ganapati (head of Siva ganas)
Gajanana (one with elephant face)
Vigneshwara (one who removes obstacles)
Pilliar
Vinayagar

Ganesha Gayatri mantram
om tat purushaaya vidmahae
vakra dhundaaya dheemahi
tanno dhandhi: prachodayaat