Karaite Judaism or Karaism (also spelt Qaraite Judaism or Qaraism), is a Jewish religious movement characterized by the recognition of the Tanakh alone as its supreme authority in Halakha (Jewish religious law) and theology. It is distinct from mainstream Rabbinic Judaism, which considers the Oral Torah, as codified in the Talmud and subsequent works, to be authoritative interpretations of the Torah. Karaites maintain that all of the divine commandments handed down to Moses by God were recorded in the written Torah without additional Oral Law or explanation. As a result, Karaite Jews do not accept as binding the written collections of the oral tradition in the Midrash or Talmud.
During the 9th century C.E., a number of sects arose that denied the existence of oral Torah. These sects came to be known as Karaites (literally, People of the Scripture), and they were distinguished from the Rabbanites or Rabbinical Judaism.
The Karaites believed in strict interpretation of the literal text of the scripture, without rabbinical interpretation.They believed that rabbinical law was not part of an oral tradition that had been handed down from G-d, nor was it inspired by G-d, but was an original work of the sages. As such, rabbinical teachings are subject to the flaws of any document written by mere mortals.
The difference between Rabbanites and Karaites that is most commonly noted is in regard to the Sabbath: the Karaites noted that the Bible specifically prohibits lighting a flame on the Sabbath, so they kept their houses dark on the sabbath. The Rabbanites, on the other hand, relied upon rabbinical interpretation that allowed us to leave burning a flame that was ignited before the sabbath. Karaites also prohibited sexual intercourse on the sabbath, while Rabbanites considered the sabbath to be the best time for sexual intercourse. The Karaites also follow a slightly different calendar than the Rabbanites.
According to the Karaites, this movement at one time attracted as much as 40 percent of the Jewish people. Today, Karaites are a very small minority, and most Rabbinical Jews do not even know that they exist. A Karaite community existed in Egypt until the Six Day War A somewhat sizable community still lives in Los Angeles.
Sources: Judaism 101