Here's why:

* Photo- refers to light.

* Auto- means self.

* Troph- relates to nourishment.

So, a photoautotroph is an organism that makes its own food (nourishment) using light.

The process they use is called photosynthesis, where they convert light energy into chemical energy stored in the form of sugars (like glucose).

Examples of photoautotrophs include:

* Plants

* Algae

* Cyanobacteria