Skip to why it's OK to do so: 'demon' refers to software demons, not spiritual demons. Otherwise, read on through the longer text ...
Some will quote I Cor 10:20, "I do not want you to be partners with demons" - with obvious apparent relevance to the issue we are addressing. Some will quote Rom 14 about not 'offending' a brother by eating food that is unclean, suggesting that our use of this internet provider might 'offend' some.
Others will quote I Tim 4:4, "Everything that God has created is good; nothing is to be rejected, but everything is to be received with a prayer of thanks." And some will quote William Booth saying "Why should the devil have all the good music" when people criticized him for the Salvation Army bands which used the popular music of the time.
And there is the danger that if we take what is supposed to be a joke too seriously then we will turn people away from God more effectively than by using an internet provider with a dubious name. So how do we resolve this issue?
Well, it might help to understand not only what Paul is talking about in his letters above, but also the meaning of the word 'demon' in computers.
They are described in the New Testament of the Bible in these roles, but the Bible does not give us much to go on. Writers like Kurt Koch have documented their activity carefully. But much Christian thought that has been devoted to them has been imagination and speculation, of varying degrees of quality.
Some writings by Christians, such as Piercing the Darkness by ====, show demons as cynical destroyers and manipulators or people and as warriors of the enemy against God. Though Christian in terminology, such writing is often pagan in underlying worldview, setting forth a universe in which the real action is of demons versus angels and humans are stupid, tiny pawns in the process, whose main contribution to the side of good is to provide 'prayer fuel' for the angels! However, there seems to be some truth in the view of demons being destroyers of people and antipathetic towards God.
C.S. Lewis, in his famous Screwtape Letters, showed demons (he called them devils) as highly intelligent planners and interferers in people's lives and beings. They have aims, their main one being to try to get people away from God and keep them away. Lesser aims include human misery, disease and suffering, with wars being particularly relished. Lewis's view, which very much a work of fantasy and imagination, seems much closer to the overall biblical 'feel' concerning demons.
Whatever the truth, demons are destructive of all that is wholesome and good, and have a power over human beings that can only be resisted fully under the authority of Jesus Christ. (It has been claimed that demonic activity is consistent with every religion on earth, except for biblical Christianity and some forms of Judaism. Source unknown.) Therefore the church can (should) have no links with them.
Display "Warning: The fluid is getting too hot"
AsSoonAs Temperature > 150
That would be a demon. It has two parts: the instruction(s) (in this example the Display statement) and a condition that can be either true or false. Both the instruction part and the condition can be much more complex. Demons differ from ordinary programs in that ordinary programs are activated in sequence, one after the other, while demons are activated sporadically, when and only when their conditions become true - which might be never or many time a second.
Demons were first used widely in artificial intelligence, because a set of demons is able to respond 'intelligently' to a wide variety of conditions. They are now used a lot in internet software, which has to have just this capability - to respond to the modem line going down, a new user logging on, users doing unpredictable things at unpredictable times, web pages being asked for, and so on.
That is why one internet provider called itself 'demon'.