Strace is a powerful diagnostic tool used in Linux and other Unix-like operating systems. It allows users to monitor the interactions between a program and the operating system by tracing system calls made by the program. This can help developers and system administrators understand how a program operates, identify performance issues, and debug errors. By using Strace, users can see detailed information about each system call, including the arguments passed and the return values. This information is invaluable for troubleshooting and optimizing applications, making Strace an essential tool for anyone working with system-level programming or application development.