The concept of computer hardware and software 1.1.1
Computer systems consist of hardware and software.
The computer software is divided into two categories: system software and application software.
- System software: manage the entire computer system, process monitoring computers running the system resources are reasonable dispatch, efficient operation.
- Applications: various programs according to the task needs of users compiled.
Hierarchy 1.1.2 computer system
The hierarchy of a computer system evolved so far, can be summarized into six levels.
In the early days of computers, only the machine language, the figure above collectively referred to as M0 and M1 the actual machine (machine language machine), the user must use binary code transmission instruction, very difficult.
Further, in order to solve this difficulty computer users point, assembly language (symbolic programming language) emerged, which symbol ADD SUB \ MUL \ DIV, respectively, represent the arithmetic \, and instructions or data using symbols where address storing means, the program is no longer using the binary cumbersome to write programs. But in fact, that no machine can directly identify the assembly language, it is necessary to assembly language program translated into machine language program to be accepted and the machine runs automatically. This is a machine translation system software assembler to complete.
Due to the use of assembly language or machine language need to know a lot, and this language is not universal, each corresponding machine language is not the same, so in order to be more convenient for people to use computers, giving rise to a high-level language. High-level language such as (FORTRAN \ BASIC \ PASCAL ...) this type of language is very close to people's habits, and the lower threshold, the programmer only needs to master syntax and semantics of such high-level language can use this programming language. Of course, the machine itself does not recognize same high-level language, because of the need to convert high-level language into assembly language (M4 re-done) and then translated into machine language before running. Here high-level language into assembly language software program called translation. Translation program is divided into two: one is the compiler, the other is the interpreter. Difference between the two is that the compiler is to compile the complete unit-level language program and then run as long as the source code unchanged do not need to be re-compiled. The interpreter is a one run, and the run will need to be translated every time.
And back to the figure we can see that there is an application language machine (M5), this level is to make the computer meets certain uses specially designed, placed today, it is mainly used in development of artificial intelligence.
The bottom of the microprogram machine that is separate from conventional machines, is to separate the machine language statements, each of M1 to translate into a single machine instruction set of microinstructions constituting a microprogram.
1.1.3 Computer Organization and Computer Architecture
The computer architecture refers to those properties of the computer system can be seen programmers, i.e., structural and functional characteristics conceptual.
Computer Organization refers to how a computer system embodied in the property, which contains many of the programmers is transparent to the hardware details .