What distinguishes a compiler from an interpreter?

A compiler is distinguished from an interpreter primarily by its method of translating source code. A compiler translates the entire source code into machine code or a binary format before the execution of the program begins. This means that the compilation process happens in one go, generating an executable file that can be run multiple times without the need for recompilation, which typically leads to improved performance during execution.

The process involves various stages such as lexical analysis, syntax analysis, semantic analysis, optimization, and code generation, culminating in a final output that represents the program in a form that the computer can understand and execute. This entire compilation process also allows for error checking at the time of compilation, which can help catch issues early in the development cycle.

In contrast, an interpreter processes the source code line-by-line or statement-by-statement during execution. This means that the source code is executed directly without producing a separate machine code file. As a result, interpreters can potentially introduce overhead during runtime, as each line of code is parsed and executed in real-time.

Each option pertains to specific characteristics of compilers and interpreters, and the essence of the difference lies in how and when the source code is translated and executed.