What is the purpose of atomic variables in multithreaded applications?

Atomic variables in multithreaded applications provide read and write operations that are performed as indivisible (atomic), meaning without interruption and interference from other threads.

This is important to prevent race conditions, where multiple threads attempt to modify the same variable simultaneously.

For example, in Java, the AtomicInteger class allows safely incrementing a counter without using locks:

import java.util.concurrent.atomic.AtomicInteger;

AtomicInteger counter = new AtomicInteger(0);

// Atomically increment the value
counter.incrementAndGet();

Using atomic variables improves performance compared to synchronization, as operations are implemented at the processor level and do not require locks.