The smoother the surface the faster it is. Polished hardwood, such as a Basketball court is the fastest surface I have played on. Smooth polished cement/concrete is a close second. After these unusual surfaces, various hard court surfaces are fast depending upon the amount of grit used in the surface treatment and the wear on the court. Grass is also quite fast especially if damp, but not wet and maintained short enough. Of the normal ATP surfaces well maintained grass courts are likely the fastest.
Because it is
153mph
The first surface tennis was played on was grass
Rafael Nadal.
echizen ryoma
Badminton is... not tennis
Aaron Savannah
Serena Williams Venus Williams
Andy Roddick at 166.3 MPH
The fastest ever serve recorded; 251 Km/h, was by Ivo Karlovic.
Jai-alai
Men's tennis.