Intake, or Inlet, is an important part of air-breathing engines. In this course, the concepts, principles and applications of intakes are introduced. Topics include subsonic intakes, supersonic intakes, characteristics under off design conditions, boundary layer control, distortion and swirl, and wind-tunnel testing and analysis. The course objectives include: develop comprehensive knowledge in the fundamental principle of intake; master the aerodynamic analysis methods; acquainted with the procedures of intake design; provide foundations for studying follow-up courses and carrying out scientific research.