BPF, or Berkeley Packet Filter, is a technology used in computer networking to capture and filter network packets. It allows programs to efficiently analyze network traffic by specifying which packets to capture based on certain criteria, such as source or destination addresses. This capability is essential for network monitoring and security applications. Originally developed for the Unix operating system, BPF has evolved into a powerful tool used in various systems, including Linux. It enables developers to write custom filtering rules, making it easier to manage and analyze large volumes of network data without overwhelming system resources.