eBPF (extended Berkeley Packet Filter) is a technology that allows developers to run custom code in the Linux kernel without changing the kernel source code or loading kernel modules. It provides a safe and efficient way to extend the functionality of the operating system, enabling features like network monitoring, performance analysis, and security enhancements. By using eBPF, developers can write small programs that are executed in response to specific events, such as network packets being sent or received. This capability makes it easier to implement advanced features like observability and security policies while maintaining system stability and performance.