Flag is a symbol of extreme faith. The 2 pennants represent the mountains of the nation and the 2 major religion of the country they are Hinduism and Buddhism . The blue and crimson red colors of flag represents various meaning; Crimson red represents the brave spirit of Nepalese. Blue border signifies peace of a country and the great sky, the vast ocean, intense cold, calmness and wisdom or knowledge. White color reflects Nepal’s neutrality. The sun and moon represents the hope that Nepal will last till the sun and moon is there in the sky.
It is only one of the national flag in the whole world which is non rectangular in shape.
Citation: All over from various links