There are many different types of transistors, and many variations on the symbol to represent them. There are also other ICs that come in the same package. Here we see a few common ways of drawing bipolar and MOSFET transistors.
0:00 Bipolar Transistor
0:53 Mosfet Transistor
1:32 Read labels to differentiate betweens standard packages
2:09 Voltage Regulator
3:10 Transistor with a different package