How does `sync/atomic` differ from `sync.Mutex`?

Atomic operations are low-level, lock-free hardware instructions. Mutexes are higher-level software locks managed by the OS/Runtime.

The sync/atomic package provides CPU-level instructions (like Compare-And-Swap) to mutate integers and pointers safely without blocking the thread. It is immensely faster than a Mutex but limited to simple types. Mutexes are required when executing blocks of logic or mutating complex data structures.