Jehovah's Witnesses, contrary to what some ignorant individuals will undoubtedly come along and say, are NOT a cult. Their way of worship is modeled after that of the established first century Christian congregation. Their teachings, beliefs, practices, etc...are based entirely on the scriptures. They recognize the important of using God's personal name, Jehovah, in worship today and yearly spend over ONE BILLION hours in their global Bible educational work.
They currently number over 6.5 million active members worldwide and are active in preaching in over 235 lands. They do NOT teach or believe in unscriptural doctrines of man such as the trinity, hellfire, the immortality of the soul, and so forth.
Jehovah's Witnesses recognize that Jehovah God alone is the Universal Sovereign and Almighty God. They recognize that Jesus Christ is the first of God's creations, and the second-most powerful being in the universe next to God himself. They recognize from the scriptures that the holy spirit is not a being in itself, but God's active force, or his means of accomplishing his will.
They recognize from the scriptures that God's original purpose for humanity was to enjoy eternal life here on earth in perfection and in a paradise setting. They know that God's purpose has not changed and that in the very near future, God will be intervening in mankind's affairs to the point of destroying all earthly governments and using his Kingdom (currently presided over by his Son, Jesus) to usher in the world that humans were meant to have.
Jehovah's Witnesses, again, are NOT a cult, they do not brainwash its members, they simply explain Bible teachings to people in a way that is easy to understand and will help them to appreciate that living by Jehovah God's standards as set forth in the Bible is the only way to have a truly happy and successful life. To find out more about them, please check their official website below, which has a large number of answers to your questions.