Many people have not heard of the term "deism." Those that have are probably not familiar enough with it to explain what it is. I would like to take a moment and go over deism in depth, and shed some light as to why it is growing at a rate of 700% per year (US statistics).
Deism is a natural religion. That means that all you have to do to believe in God is to look at the world around you. God is viewed as the creator. Life as we know it did not happen by random chance. Someone, or something, designed it all. There are no deistic prophets that had revelations from God, there is no deistic bible, and no official church. It is not a religion, but rather a philosophy that individuals adhere to, much like Buddhism. Many deists consider themselves spiritual, but not religious.
Deism gained prominence during the Age of Enlightenment, a time period in Europe and the USA, between the 1600s and 1700s. Intellectuals started asking questions, looking for answers, and promoting individualism. Science, they realized, could explain many things that religion could not, or that religion contradicted scientific observations. Religious traditions went by the wayside, and scholars started looking to human understanding and reason. "Moses did not have a telescope" is a classic talking point of deism.
Deism is a very broad umbrella term by itself. There are two main subcategories of deism: classical and modern. There are other subcategories, but let's focus on these two for now.
Classical Deism
This is typically the view that God is the creator of life, the universe and nature. He made natural law, set everything in motion and then walked away, having nothing to do with humans, the earth, or the universe. He does not answer prayers, He does not interfere, and He does not perform miracles. Classical deists reject revealed religions (Judaism, Christianity, Islam), holy books, and divine revelation (prophets are always alone when receiving divine revelations...no witnesses). Many of the Founding Fathers of the USA were classical deists, most notably Thomas Jefferson and Benjamin Franklin.
Modern Deism
This philosophy shares many beliefs with classical deism, but expands on some of them. God did not abandon us and walk away. He gave us free will and He does not interfere with it. That is why He does not answer prayers, perform miracles or give divine revelation. To do so means it is no longer free will. He cares about us, He watches the world and universe to see how we evolve, yet He has a "look but don't touch" approach.
Deists typically do not believe in the supernatural. There is no devil, demons, magic, boogie men, etc. There is no evil force working against us. Bad things happen because either someone chose to do something bad (murder), or nature is just following its course (tornado).
Deistic views on the afterlife will vary from person to person. Some believe that there is life after death and/or a paradise, others believe that death is the end; game over. Deists understand that the afterlife can't be proven one way or another, so they try to focus on living morally in the here and now, and "hope for happiness beyond this life" (Thomas Paine, The Age of Reason).
Prayers can be recited as a deist, however, since God does not interfere with free will, those prayers are usually "giving thanks" instead of "asking for something." Free will is not something that is limited to just you in the present. If your ancestors did something that affects you today (think genetics), God won't interfere.
From here, deism breaks down into further subcategories. Some people claim to be a Christian deist, and while that may seem like an oxymoron, when understood in context it actually works. They believe in God and that Jesus was a prophet. His messages are an example to live by, and it is to that end that they follow Him. He was a man who did die on the cross during the time of the Roman Empire. Whether or not He was the divine Son of God is a belief that is up to the individual. They still reject organized religion (denominations), and tend to view the Bible as a collection of stories that are allegorical, metaphorical, poetry or simply early literature. Others believe in pandeism (God became the universe) or panendeism (the universe is a part of God, but God is still a separate entity).
Regardless of personal beliefs, deists have no problems with science and technology. They view knowledge and wisdom to be attributes of progression. God gave us the ability to reason, and so we should.