  Properties of disordered thin films are discussed based on the viewpoint that
superconducting islands are formed in the system. These lead to superconducting
correlations confined in space, which are known to form spontaneously in thin
films. Application of a perpendicular magnetic field can drive the system from
the superconducting state (characterized by phase-rigidity between the sample
edges) to an insulating state in which there are no phase-correlations between
the edges of the system. On the insulating side the existence of
superconducting islands leads to a non-monotonic magnetoresistance. Several
other features seen in experiment are explained.
