The subject can be hard in this time of pandemic, but we are learning every detail in order to apply it in real life. Signal Processing focuses on analysing, modifying, and synthesizing signals such as sound, images, and scientific measurements. it also condenses measurements to extract information about some distant state of nature. Signal processing can be described from different perspectives. To an acoustician, it is a tool to turn measured signals into useful information. To a sonar designer, it is one part of a sonar system. To an electrical engineer, it is often restricted to digitization, sampling, filtering, and spectral estimation.