Chapter 15
The focus in this chapter is on speed and on why compiled programs are faster than interpreted
ones, and why some algorithms are faster than others.
In section 15.2 we introduce machine language and give some examples of it. We create a
simple graphical language and both an interpreter and compiler for it. We explain that when
Java was first created the Java source code was compiled to byte codes for a virtual machine and
then the Java Virtual Machine interpreted the virtual machine byte codes. These days the Java
In section 15.3 we cover what makes a computer fast or slow and ways to compare two
computers. It is useful to have students pick a computer from 2-3 choices for some task and then
have them justify their choice.