Circuit Theory/Transistor symbols
There are lots of different types of transistors. The most popular is a MOSFET and within this family there are lots of possibilities. The goal right now is not to understand the differences and what all the lines mean. Look at them and see that normally there are three wires associated with them.
|JFET||MOSFET enh||MOSFET enh (no bulk)||MOSFET dep|