Levitation is the power to magically propel yourself into the air without the use of tools or assistance from another person or being. This becomes Phoebe Halliwell's second power in the series and her first active ability. This power was later taken away for Phoebe's abuse of her magic.
Phoebe's levitation power was normally activated by lifting her arms into the air, or at least her forearms, and allowed her to combine her martial arts skills with her magic, allowing her to effectively fight demons alongside her sisters.
When she originally received her ability, she had a lack of fine control over it, sometimes not being able to get up into the air while other times she could not get down without assistance. Also, she could not move through the air unless she had previous inertia behind her or had assistance, such as when Prue used her telekinesis to propel her sister in the episode. This is not always the case considering that we see a girl in Magic School floating through the hallways without any seemings previous force behind her. This also could've been the similar power of hovering.
At one point in the series, it is seen that Phoebe can use her levitation while doing something else, some of which require her to not focus on actually using the power, such as meditating.
In the Season Three episode the girls face a feline warlock familiar with the power of Projective Levitation, stolen from a witch. Using this power the warlock, Shadow could cause other things and people (in one case more than one of the same time) to levitate however it is not known if he could himself levitate.