Here's why:

* Ribosomes are the protein factories of the cell. They are responsible for translating the genetic code from messenger RNA (mRNA) into a chain of amino acids, which then fold into functional proteins.

* They are small and round, typically about 20-30 nanometers in diameter.

* They can be found in both prokaryotic and eukaryotic cells, although their structure and composition differ slightly between the two types of cells.

Let me know if you have any other questions about ribosomes or protein synthesis!