Lord Ganesha is believed to have killed demons named, Ahantasur (symbolized 'Ego'), Mayasur (symbolized 'Delusion'), Lobasur (symbolized 'Greed'), Kamasur (symbolized 'Work'), and Krodhasur (symbolises 'Anger').
Another noted fact is that people avoid seeing Moon, during Ganesha Chaturthi. It is said that once, moon burst into laughter on seeing a hefty, elephant-face Lord Ganesha. Lord Ganesha on seeing this cursed him that if anyone would see moon between Ganesha Chaturthi till Anant Chaturdasi, they will have to endure problems and predicaments in their life.
Lord Ganesha is also stated to be, 'The God for Everybody'. He is seen riding his favourite mouse, which symbolises wandering of mind, desire etc. Lord Ganesha hence rides the mouse to keep all these under his control.