The development of language processing programs has gone through three stages of development: machine language, assembly language and high-level language; machine language is a program language or instruction code that can be directly recognized by the machine; assembly language is any kind of programming language used in electronic computers. , a low-level language for a microprocessor, microcontroller, or other programmable device; a high-level language is a machine-independent, process- or object-oriented language.
The operating environment of this article: Windows 7 system, Dell G3 computer.
The development of language processing programs has gone through three development stages: machine language, assembly language and high-level language.
The first stage: machine language
Machine language is a programming language or instruction code that the machine can directly recognize without translation. Each operation code is written inside the computer. There is a corresponding circuit to complete it, or it refers to a programming language or instruction code that can be directly understood and accepted by the machine without translation. Machine language uses absolute addresses and absolute opcodes. Different computers have their own machine languages, that is, instruction systems. From a usage perspective, machine language is the lowest level language.
Second stage: Assembly language
Assembly language (Assembly Language) is any programmable language used in electronic computers, microprocessors, microcontrollers or other The low-level language of the device, also known as the symbolic language. In assembly language, mnemonics are used to replace the opcodes of machine instructions, and address symbols or labels are used to replace the addresses of instructions or operands. In different devices, assembly language corresponds to different machine language instruction sets, which are converted into machine instructions through the assembly process. There is a one-to-one correspondence between a specific assembly language and a specific machine language instruction set, and they are not directly portable between different platforms.
The third stage: high-level language
High-level language (High-level programming language) is a machine-independent, process- or object-oriented language. A high-level language is a language designed with reference to mathematical language that approximates daily conversation. For example, to add two variables and assign them to a third variable, it is expressed in high-level language as var3=var1 var2.
Expand knowledge: The difference between machine language, assembly language and high-level language
1. Efficiency:
Machine language: high execution efficiency and fast speed;
Assembly language: low programming efficiency, low-level language;
High-level language: lower execution efficiency than machine language, but high programming efficiency in assembly language.
2. Composition:
Machine language: Machine language is an instruction set composed of 0 and 1 arranged according to certain rules: it is the only one that a computer can recognize and execute. language.
Assembly language: An instruction system that uses mnemonics to represent opcodes and operands in machine instructions. Enhanced readability and fast execution speed;
High-level language: a language that is closer to human natural language and mathematical language. Programs written in it can greatly reduce the labor of programmers, so it also has Better portability.
3. Oriented type:
Machine language: It is a machine-oriented language with poor readability.
Assembly language: It is still a machine-oriented language with strong readability;
High-level language: Simplified natural language that is close to humans and has high readability.
4. Different characteristics
Machine language:
The advantage is direct execution, fast speed and low resource usage. The disadvantages are poor readability and portability, and complicated programming.
Assembly language:
The characteristic of assembly language is that it is easy to be recognized and executed by the computer. Using it for programming can reduce the space occupied, increase the running speed, and directly control the hardware. When real-time control is required, it plays an irreplaceable and important position, but assembly language is more complex and difficult to program and understand, especially when performing data processing or logical operations, its disadvantages are highlighted.
High-level language:
can be more accurately understood by programmers. It has strong expressive ability, many functions, high programming efficiency, fast learning speed, and high degree of automation. In most software development, users use high-level language programming to improve programming efficiency. However, when the storage space is small, the execution speed is fast, and the hardware needs to be directly controlled, assembly language programming is used to optimize the program speed.
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