Internet browser that includes an enhanced cache for user-controlled document retention

A browser for requesting and receiving documents from a network includes a cache which stores a plurality of documents and has a user-defined storage limit. At least one of the plurality of documents stored in the cache is designated as a keep document. When a document is requested and received from the network, it is stored in the cache. The cache then determines whether the amount of storage used by the cache exceeds the storage limit. If the storage limit is exceeded, the cache deletes the oldest documents not designated as keep documents until the amount of storage used by the cache is within the storage limit.