The document discusses internet congestion, defining it as when a network node or link is carrying more data than it can handle, resulting in reduced quality of service. Examples of congestion given include slow loading of pages during high traffic periods like sales events. Causes of congestion outlined include low bandwidth, the Border Gateway Protocol prioritizing shortest paths over available bandwidth, and network protocols exacerbating congestion through aggressive retransmissions. Methods to control congestion involve reducing unnecessary content, using more efficient file formats, and improving network infrastructure and protocols.