The word "swastika" comes from the Sanskrit svastika - "su" meaning "good," "asti" meaning "to be," and "ka" as a suffix.
Until the Nazis used this symbol, the swastika was used by many cultures throughout the past 3,000 years to represent life, sun, power, strength, and good luck.
From Sanskrit स्वस्तिक (svástika), from सु (sú, “good, well”) + अस्ति (ásti-), a verbal abstract of the root of the verb "to be", svasti thus meaning "well-being" — and the diminutive suffix क (-ka); hence "little thing associated with well-being", corresponding roughly to "lucky charm".
Hitler hijacked the swastika from the Hindu's and Budhhists (and native American Indians).
The right-hand swastika is one of the 108 symbols of the god Vishnu as well as a symbol of the sun and of the sun god Surya. The symbol imitates in the rotation of its arms the course taken daily by the sun, which appears in the Northern Hemisphere to pass from east, then south, to west. (It is also a symbol of the sun among Native Americans.)
The left-hand swastika (called a sauvastika) usually represents the terrifying goddess Kali, night and magic. However, this form of the swastika is not "evil" and it is the form most commonly used in Buddhism.