In C and C++, memory management is a manual process handled by the programmer. In C, memory is allocated and freed using functions like malloc and free, while in C++, memory management involves the use of operators such as new and delete. Proper management is crucial to avoid memory leaks, segmentation faults, or other issues related to memory allocation. Java, on the other hand, manages memory automatically with a garbage collector that periodically removes unused objects, which simplifies memory management for developers. This automated system in Java reduces the chances of memory leaks, helping developers focus more on application logic rather than managing memory manually.