Here's a breakdown:

* Photo- refers to light.

* Auto- means self.

* Troph- relates to nourishment.

So, a photoautotroph is an organism that makes its own food using light energy. This process is called photosynthesis, where they use sunlight, water, and carbon dioxide to produce sugars (their food) and oxygen as a byproduct.

Examples of photoautotrophs include:

* Plants

* Algae

* Cyanobacteria