Streaming instability is a phenomenon that occurs in a wide range of astrophysical and geophysical systems, where particles with different velocities interact with each other. This instability can lead to the formation of clumps or structures within the system, which can have significant implications for the evolution and dynamics of the system. One of the most well-known examples of streaming instability is the formation of planetesimals in protoplanetary disks during the process of planet formation. In this case, dust particles within the disk collide with each other and form clumps due to the streaming instability, eventually leading to the formation of larger bodies such as asteroids and planets. Streaming instability has also been observed in other systems such as granular materials, dusty plasmas, and even in the context of traffic flow. Understanding the mechanisms and properties of streaming instability is therefore crucial for studying a wide range of natural and artificial systems.