The tanto knife has a high point with a flat grind, leading to an extremely strong point that is perfect for stabbing into hard materials. The thick point of the tanto blade contains a lot of metal near the tip, so it is able to absorb the impact from repeated piercing that would cause most other knives to break.
The front edge of the tanto knife meets the back (unsharpened) edge at an angle, rather than a curve. As a result, the tanto blade does not have a belly, which is sacrificed in exchange for a stronger tip. Because it lacks a belly for slicing, it is not useful as a general utility knife. However, it's extremely strong point allows it to be used in tough situations where piercing hard materials is required.