AddressSanitizer is a memory error detection tool designed to identify issues such as buffer overflows and use-after-free errors in programs. It works by instrumenting the code during compilation, adding checks that monitor memory access patterns. This helps developers catch bugs that could lead to crashes or security vulnerabilities. Primarily used in C and C++ programming, AddressSanitizer is integrated into popular compilers like GCC and Clang. When a memory error is detected, it provides detailed reports, making it easier for developers to diagnose and fix the underlying problems in their code.