CETEL is the YouTube channel: Chemical Engineering Through E-Learning opened to share the knowledge non-profitably. The uploaded videos are aimed to provide an insight knowledge to the students without money minded. This video class helps to understand the principles of a compressor working under reversible isothermal compression. Types of compressors is explained. Equations to estimate the minimum amount shaft work required to compress the air or gas from given initial pressure to its final pressure is established under reversible isothermal condition.