What is the difference between competition and parallelism in the Go language?

In Go, concurrency and parallelism are related but different concepts.

• Concurrency means the ability of a program to manage multiple tasks that can be executed simultaneously, but not necessarily on different cores. In Go, this is achieved using goroutines (goroutines), which allow functions to be started, paused, and resumed, effectively switching between them.

• Parallelism is the simultaneous execution of multiple tasks on different processor cores.

Example: if you have 4 cores, Go can run 4 goroutines in parallel, utilizing all cores. If there are fewer cores, goroutines will compete for processor time, switching between them.

Thus, concurrency is about the program structure and task management, while parallelism is about the physical simultaneous execution.