Assembly language programs consist of three types of statements −

• Executable instructions or instructions,
• Assembler directives or pseudo-ops, and
• Macros.

The executable instructions or simply instructions TELL the PROCESSOR what to do. Each instruction CONSISTS of an operation code (opcode). Each executable instruction generates one machine language instruction.

The assembler directives or pseudo-ops tell the assembler about the VARIOUS aspects of the assembly process. These are non-executable and do not GENERATE machine language instructions.

Macros are basically a text substitution mechanism.

Assembly language programs consist of three types of statements −

The executable instructions or simply instructions tell the processor what to do. Each instruction consists of an operation code (opcode). Each executable instruction generates one machine language instruction.

The assembler directives or pseudo-ops tell the assembler about the various aspects of the assembly process. These are non-executable and do not generate machine language instructions.

Macros are basically a text substitution mechanism.