  The main purpose of this brief review is to present a sketch of the mechanism
of high-Tc superconductivity based mainly on tunneling measurements in
cuprates. In the review, we shall mostly discuss tunneling spectroscopy in
Bi2212. Analysis of the data shows that the Cooper pairs in cuprates are
topological excitations (e.g. quasi-one dimensional bisolitons, discrete
breathers etc.), and the phase coherence among the Cooper pairs appears due to
spin fluctuations.
