The six jumps
Figure skating has six standard jumps. They all land the same way — backward on an outside edge — so the difference is entirely in the takeoff.
Toe jumps
The toe loop, flip and Lutz are toe-assisted: the skater taps the ice with the toe pick of the free foot to launch.
The flip and Lutz are easy to confuse. Both take off backward with a toe pick assist, but the flip leaves from a back inside edge and the Lutz from a back outside edge, against the direction of rotation.
Edge jumps
The Salchow, loop and Axel take off from an edge without a toe pick.
The Axel is the only jump that takes off going forward. Because the skater still lands backward, it carries an extra half rotation: a single Axel is one and a half turns, a triple Axel three and a half.
Why edges matter to the score
Judges watch the takeoff edge closely. A Lutz that drifts onto an inside edge before leaving the ice is marked as an edge call and loses value, even if the rotation and landing are clean.