BASIC is a language
that is usually implemented with an interpreter.
In general, a program executed by an interpreter will run more slowly than a program that is first compiled
into object code. The reason, of course, is that the interpreter must analyze each line and convert each line to
machine code each time the program runs.
On the other hand, interpreters have other compensating advantages in some situations. For instance, when
students are learning to program, the interactivity of an interpreter, and the savings of recompilation time on
long programs, can be more important than final execution speed. Interpreters often can provide better diagnostic
messages, too, since they work directly from the source code, line by line. In addition, with the continuing
increases in hardware computation speeds, speed of execution sometimes becomes less important to users than
other features of a language.
The distinctions are sometimes ???fuzzy.??? First of all, some languages are implemented both as interpreted
and compiled languages (e.g., BASIC, PERL, LISP). The modern Java language also blurs compiler/interpreter
boundaries, as we will now discuss.
VIRTUAL MACHINES
Java is both compiled and interpreted.
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