Article history on Web

[cirosantilli]

https://en.wikipedia.org/wiki/Wikipedia:Pruning_article_revisions explains how Wikipedia saves space:

The revision count is not a technical or cost problem. The Wikimedia servers combine old versions into large batches and then compress them. Because so much is the same between revisions the compression produces a huge reduction in storage space. The storage space is almost free because starting in late 2004 and early 2005 Wikimedia uses SATA hard disks on some of the web server for this work. The SATA disks are extremely cheap and because the servers are already used for page building there is insignificant additional cost there. As with the main database servers, several copies of each set are kept so that failure of one machine will not cause trouble.