Assembly language

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An assembly language is a programming language that can be used to directly tell the computer what to do. An assembly language is almost exactly like the machine code that a computer can understand, except that it uses words in place of numbers. A computer cannot really understand an assembly program directly. However, it can easily change the program into machine code by replacing the words of the program with the numbers that they stand for. A program that does that is called an assembler.

Programs written in assembly language are usually made of instructions, which are small tasks that the computer performs when it is running the program. They are called instructions because the programmer uses them to instruct the computer what to do. The part of the computer that follows the instructions is the processor.

The assembly language of a computer is a low-level language, which means that it can only be used to do the simple tasks that a computer can understand directly. In order to perform more complex tasks, one must tell the computer each of the simple tasks that are part of the complex task. For example, a computer does not understand how to print a sentence on its screen. Instead, a program written in assembly must tell it how to do all of the small steps that are involved in printing the sentence.

Such an assembly program would be composed of many, many instructions, that together do something that seems very simple and basic to a human. This makes it hard for humans to read an assembly program. In contrast, a high-level programming language may have a single instruction such as PRINT "Hello, world!" that will tell the computer to perform all of the small tasks for you.