IPC is a mechanism that allows processes to exchange data and signals in an operating system. Processes may need to communicate to share resources, synchronize tasks, or distribute workloads efficiently. IPC can be achieved using various techniques, including message passing, shared memory, pipes, sockets, and signals.

There are five major ways by which IPC is achieved and below are their description:

1. Message Passing: Processes communicate by sending and receiving messages via the kernel. Message queues are used and implemented using linked lists in the kernel space. Example: Client-server communication in cloud applications, such as order processing systems in e-commerce platforms. OS Example: Windows Message Queuing in Windows OS.

2. Shared Memory: Processes access a common memory space for fast communication. Implemented using memory buffers and managed using page tables. Example: Modern web browsers like Chrome use shared memory for communication between rendering and networking processes. OS Example: System V Shared Memory in Linux and UNIX.

3. Pipes and Named Pipes: there are a unidirectional or bidirectional channel for data flow between processes. They are implemented using circular buffer. Example: The Linux | (pipe) operator (ls | grep txt) for command-line operations. OS Example: Named Pipes in Windows and anonymous pipes in UNIX/Linux.

4. Sockets: Used for IPC over networks. Socket buffers and queues are used for implementation. OS Example: Berkeley Sockets in UNIX/Linux and Winsock in Windows. Processes notify each other using lightweight signals.

5. Signals: Processes notify each other using lightweight signals. Implemented using signal handler tables. Example: SIGTERM is used to terminate a process in Unix-based systems. OS Example: POSIX signals in UNIX/Linux.

Efficient IPC mechanisms are necessary for modern operating systems, that enable multitasking, distributed computing, and real-time applications.