Biology is the study of life, their chemistry, their evolution, and how they are scientifically classified. It is easy to think of biology as all living things, from the microscopic bacteria and viruses that make us sick to the giant elephants that roam Africa.
In its most basic form, all living things are made out of cells.
A Eukaryotic cell is pictured above along with its components. source There are two different types of cells, eukaryotic and prokaryotic. The main difference is that eukaryotic cells (which make up animals, plants, you and me) have a membrane bound nucleus while prokaryotic cells (smaller, bacteria, single celled organisms) do not have a membrane bound nucleus.
But we will discuss cells more indepth at another time. Enjoy viewing some of the links I have added below for you to better understand science. Do not feel overwhelmed, we will go into depth of many of these subjects. You can use these as references if you have questions.