I disagree with Queequeg's assertion that the Toe Loop is easy to master. First a slightly more detailed description is in order.
The skater performs a right forward inside three turn, and toes in with their left leg. After the skater toes in, their right foot is continuing along it's inside edge. Just as it crosses the left leg, the skater takes off. This is known as "the draw." You can picture this as the right foot approaching the in-air jumping position, of being crossed over the left foot and tucked in. The skater takes off from both feet. One revolution (in a single) is made, and the skater lands.
The rub is, that this jump is easy, if you don't do the draw. In this situation, you vault off of the left foot. You have performed a toe-waltz. The way to tell if it's the real-deal or if it's a toe-waltz is in the feeling (or slow motion video). You have to ask yourself: Do I feel the power of the jump come from from both feet (as with a flip) or do I feel it on just one foot?