Out in Lancelin, a french town, you have these sand dunes right next to the beach. As you can see, it looks like a desert but with white sand! In the weekends Sandgropers (slang for Western Australians) head out to these dunes and surf! They even ride on 4wd and dirt bikes performing stunts and all. Really cool.
Anyway, these rock formations are simply nicknamed pinnacles. For boring scientific explanation please proceed to the bottom of this post. Thousands of these rocks formed over the years and will continue to develop over another million years or so.
Pinnacles are actually calcium rock formations (limestone) formed over thousands of years. Experts believed that they started forming over 500 000 years ago.
If you notice, the pinnacles are all roughly the same height. If you see a few that are "taller" its because the ground you are sitting on is lower!
The top of the pinnacles all used to be 1 level. Meaning the ground "sunk" over half a million years. We always get a little bit of acid in rain and it is this chemical, Carbonic Acid that causes erosion in rocks. Rain washes away the sand however, the acid component reacts with the limestone (like you get in caves in Malaysia) and forms hardened paste which turns into these pinnacles.
In caves all around Malaysia, we get stalagmites and stalactites forming. Pinnacles are similar to that however they form from top to bottom.