TLDR: Assembly language is a low-level programming language that uses simple instructions to communicate with a computer's hardware.
Assembly language is a type of programming language that is considered low-level, meaning it is closer to the hardware of a computer. It is often referred to as assembler language or symbolic machine code. Assembly language has a strong correspondence between the instructions in the language and the machine code instructions of a computer's architecture.
In assembly language, each instruction corresponds to a specific machine instruction. These instructions are represented by mnemonic codes, which are symbolic names for the instructions. Assembly language instructions usually consist of an opcode (operation code) mnemonic followed by one or more operands. The operands can be immediate values, registers, or memory locations.
Assembly language programs are written using a series of mnemonic instructions and directives. Instructions are the actual machine instructions that the computer will execute, while directives are commands given to the assembler to perform operations other than assembling instructions. Directives can affect the object code, the symbol table, the listing file, and other aspects of the assembly process.
One of the key features of assembly language is the use of labels, which are symbolic names associated with memory locations or instructions. Labels allow programmers to refer to specific locations in the program and make the code more readable and self-documenting.
Assembly language programs are typically assembled by an assembler, which translates the mnemonic instructions and directives into machine code that can be executed by the computer. Assemblers can also support macros, which are predefined or programmer-defined sequences of instructions that can be used to simplify and reuse code.
Assembly language is specific to a particular computer architecture, as each architecture has its own set of instructions and addressing modes. However, most assembly languages can be used universally with any operating system, as they provide access to the real capabilities of the processor.
While assembly language is a powerful tool for programming at a low level, it is not as commonly used today as higher-level programming languages. Higher-level languages offer more abstraction and ease of use, allowing programmers to write code that is more portable and easier to understand.
In summary, assembly language is a low-level programming language that uses mnemonic instructions and directives to communicate with a computer's hardware. It provides a strong correspondence between the instructions in the language and the machine code instructions of a computer's architecture. Assembly language programs are assembled by an assembler and can include macros and labels to simplify and organize the code.