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Figure 1-4
Levels of Abstraction |
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languages are easier to use than assembly languages or machine code because they are closer to English and other natural languages (see Figure 1-4). |
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A program called a compiler translates programs written in certain highlevel languages (C++, Pascal, FORTRAN, COBOL, Modula-2, and Ada, for example) into machine language. If you write a program in a high-level language, you can run it on any computer that has the appropriate compiler. This is possible because most high-level languages are standardized, which means that an official description of the language exists.* |
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Compiler A program that translates a high-level language into machine code |
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*Some programming languagesLISP, Prolog, and many versions of BASIC, for exampleare translated into machine language by an interpreter rather than a compiler. The difference between a compiler and an interpreter is outside the scope of this textbook, which focuses only on compiled languages. |
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