According to the Daily Telegraph, it "sparked a revolution by becoming the first to provide genuinely affordable access to the internet in the UK".

[1][2] In 1997 Demon was bought by Scottish Telecom, a wholly owned subsidiary of the private utility company ScottishPower.

[3] In January 2019, Vodafone announced its intention to close Demon and migrate its 15,000 remaining customers to more modern services.

Dismissing the idea that the Demon name might upset those with religious convictions, Cliff Stanford laughingly said he had considered getting the numbers "666" incorporated in the dial up.

The original Demon service was hosted using mainly Apricot servers including a gigantic pair of LSI towers named "gate" and "post".

When Demon started, WinSock was still a new concept that was not widely available and MS-DOS users were generally expected to download Internet connection software based on the KA9Q implementation of TCP/IP.

All three directors were programmers and Stanford wrote many business-critical pieces of software, writing modules to adapt MMDF to Demon's purposes.

As Stanford was increasingly absorbed with corporate activities, Neil McRae eventually took over the work on the mail system.

Many other key Demon people started out as developers – Giles Todd, Clive Feather, Richard Clayton.

The company had some exposure after sponsoring Fulham F.C., but British Telecom were sceptical of Demon's projected growth and did not provide for expansion, resulting in a regular shortage of lines and regular re-digs of the top end of Hendon Lane, Finchley, north London to lay down additional cables.

[12] During 2016–2019, the Demon Internet service was slowly wound down with a view to migrating customers over to Vodafone branded products, a process that took longer than expected with some customers still being provided with Demon ADSL at the end of May 2019 due to a large backlog in the processing of migration requests.