Reddit mentions of Steampunk (Steampunk Anthologies)

Steampunk is speculative fiction set in an alternate early industrial age in which the sophistication and power of machinery is fantastically exaggerated, often with the conceit that outmoded or disproven scientific theories (aether, phlogistion, hollow Earth/lost worlds, alchemical medicine, life on Mars, etc.) turned out to be true. "Hard science fiction" steampunk typically supposes that the early mechanical computers had been successfully realized and adopted by society, so that the Industrial Revolution and the Information Age arrived in the same moment, rather than an approximate century apart.

The best get-you-up-to-speed steampunk book is the short fiction anthology simply titled Steampunk, edited by Ann and Jeff VanderMeer.

The best hard-SF steampunk is Gibson & Sterling's The Difference Engine.

Arguably the most popular steampunk "light reads" are the Parasol Protectorate series by Gail Carriger -- basically paranormal romantic comedy in a steampunk setting.

The most imaginative steampunk, in my opinion, is Jay Lake's Clockwork Earth series.

Actually reading this book right now. He says the punk term comes from the Do It Yourself attitude that the characters, stories, and fans share about creating their own little sub-culture.

Interestingly DIY was a staple of the actual Punk Rock scene of the 1960's and early 70's.