  We investigate the implications of the entropic force formalism proposed by
Verlinde. We show that an UV/IR relation proposed by Cohen et al, as well as an
uncertainty principle proposed by Hogan can be derived from the entropic force
formalism. We show that applying the entropic force formalism to cosmology,
there is an additional term in the Friedmann equation, which can be identified
as holographic dark energy. We also propose an intuitive picture of holographic
screen, which can be thought of as an improvement of Susskind's holographic
screen.
