Swastik is considered an important symbol in Hinduism and signifies prosperity and peace. ‘Swasti’ in Sanskrit means may all be well with you.
It is believed that there was once an energy explosion before there were any planets and a Solar System, hence there was a lot of energy scattered around and that is how planets and the solar system was formed. It is said that the energy was scattered in the shape of a swastika. The sign is a sort of a sun mark. We consider the Sun God very important. If he stops shining his light on us we will all perish. The four arms of Swastik stand for four main directions: North, South, East, West; the four Vedas: Rig, Sama, Yajur and Atharva; the four aims of human life called purusharthas in Sanskrit: Dharma, Artha (acquiring wealth); Kama (fulfilling desires); and finally Moksha (liberation from this earthly life.) This means the individual attaining moksha will not be born again on this earth. And the four stages of life are called ashrams – Brahmacharya, Grahasthi, Vanaprasth and Sanyasam.
Hence, this symbol is a package of everything that is a blessing to us and signifies prosperity.