Desire or enticement to do something, especially something wrong or unwise. People are tempted; we are human. We have the ability to make decisions. Good, evil, better, worse. Temptation is one influential force on our choices, usually persuading to the bad choices. There are different reasons that people are tempted.
LOTR
In The Lord of the Ring, temptation is represented in the form of the one Ring. The longer you are with it the harder and harder it becomes too resist temptation. Our ability to choose is infringed upon as a result of giving in to that temptation before. The Ring became an addiction to the people around it, so people's brains are clouded by that want for the Ring and it becomes harder and harder to let go of