Sources Of Some High-Level Language Names - Zenith Z-100 Series User Manual

Chapter 3
Table 3-1: Sources of Some High-Level Language Names
LANGUAGE NAME
BASIC
COBOL
FORTRAN
Other languages, such as Pascal, are named after people associated with
the computer industry. Still others, such as Forth, have no such roots, but
come from a term applied during the creation of the language.
High-level languages must also be converted into machine language code.
This can be done by using one of the three processes shown in Figure 3-
1: compile, interpret, or both compile and interpret (pseudo-compile).
• Compiler - A compiler will take your instructions and compile them into
machine language instructions. This may produce a certain amount of
duplication in the machine language code to handle common functions.
The result is a machine language program that will usually be
executed more slowly than a machine language or assembly
language program that does the same thing. FORTRAN and COBOL
are two examples of languages that are usually compiled.
• Interpreter - An interpreter works somewhat differently. Unlike the com-
piler, no translation takes place. Instead, the interpreter (which is a
program itself) analyzes your instructions one by one and then it (the
interpreter) completes the operation. Interpreters are usually much
slower than compilers for two main reasons: the interpreter analyzes
each instruction each time it is executed and the analysis itself
usually takes longer than the execution. However, because there is no
compilation step (as in the case of compilers), programs may be
written and tested much easier. Several versions of BASIC for the Z-
100 are interpreters. (A version of BASIC is also available as a
compiler.)
• Pseudo-compiler - A pseudo-compiler does not compile your instruc-
tions into machine code, but into a compact intermediate object code.
This code is then interpreted by a run-time program that will provide
the necessary machine instructions to complete the operation. The run-
time program executes the intermediate code in a manner similar to
that of an interpreter and, as a result, runs slower than a true compiler.
Computer Programming
SOURCE OF NAME (MEANING)
Beginner's All-purpose Symbolic Instruction Code
COmmon Business Oriented Language
FORmula TRANslator
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