MagicCards.info was a database of Magic cards similar to the Gatherer. It was used as the primary card viewer for MTG Salvation and its Wiki from 2005 to 2012 because it had the same owner. It used to be one of the most popular card searching tools on the internet thanks to its quick load speed and intricate search options, but in later years it became slower at adding new sets to its database than many other alternatives.
In August 2018, it was announced that MagicCards.info was acquired by Scryfall. Scryfall pledged to handle 99% of links from MagicCards.Info, especially any links made to card or set pages. If you would follow one of those links you would be redirected to the proper page on Scryfall or an equivalent site.