We used to believe light was a wave, then we discovered it had the properties of a particle that we call a photon. Now we know it, like all elementary quantum objects, is both a wave and a particle!
Looking to learn more about quantum physics? Here’s a selection of material to get you started.
Articles

You’ll find the latest news and articles in Scientific American’s section devoted to physics
http://www.scientificamerican.com/physics/ 
Here’s “Quantum Computing 101″ from the Institute for Quantum Computing in Waterloo, Canada
http://iqc.uwaterloo.ca/welcome/quantumcomputing101 
And all the latest quantum computing news from the techwriters at Wired
http://www.wired.com/tag/quantumcomputing/ 
What about the prospect of a quantum internet? Nature looked into it
https://www.nature.com/articles/d41586018018353 
The question is no longer whether quantum theory is correct, but what it means, contend writers at Scientific American
https://blogs.scientificamerican.com/observations/comingtogripswitht... 
Physicist and author Chad Orzel puts forward six things everyone should know about quantum physics
https://www.forbes.com/sites/chadorzel/2015/07/08/sixthingseveryonesh... 
What is quantum cryptography? Popular Science has a guide:
http://www.popsci.com/whatisquantumcryptography 
CQT's director, Artur Ekert, on quantum cryptography
http://plus.maths.org/content/os/issue35/features/ekert/index 
The New York Times reports on experiments that closed loopholes in measurements of "spooky action"
https://www.nytimes.com/2015/10/22/science/quantumtheoryexperimentsai... 
Arguments for  and against  the existence of parallel universes
https://blogs.scientificamerican.com/guestblog/areparalleluniversesu...  Current thinking about Schrödinger's cat
Books
Why not find a quantum book that suits you? Here are some reviews of good books about quantum theory:

Something Deeply Hidden by Sean Carroll
https://www.nature.com/articles/d41586019026028 
Beyond Weird by Phillip Ball
https://www.nature.com/articles/d41586018032728 
Through Two Doors at Once by Anil Ananthaswamy
https://www.goodreads.com/book/show/38527619throughtwodoorsatonce 
What is Real? by Adam Becker
https://www.nature.com/articles/d41586018037932 
The Quantum Astrologer's Handbook by Michael Brooks
https://www.theguardian.com/books/2017/nov/24/thequantumastrolgershan... 
Entanglement by Amir Aczel
https://www.publishersweekly.com/9781568582320 
Quantum by Jim AlKhalili
http://www.goodreads.com/book/show/100034.Quantum 
Quantum Theory Cannot Hurt You by Marcus Chown
http://www.independent.co.uk/artsentertainment/books/reviews/paperbacks... 
The Quantum Universe: Everything That Can Happen Does Happen by Brian Cox and Jeff Forshaw
https://www.brainpickings.org/2012/02/13/thequantumuniversebriancox/ 
The Age of Entanglement: When Quantum Physics Was Reborn by Louisa Gilder
http://www.goodreads.com/book/show/5096882theageofentanglement 
Genius: The Life and Science of Richard Feynman by James Gleick
http://www.goodreads.com/book/show/98685.Genius 
The Fabric of the Cosmos: Space, Time, and the Texture of Reality by Brian Greene
http://www.goodreads.com/book/show/22435.The_Fabric_of_the_Cosmos 
Erwin Schrödinger and the Quantum Revolution by John Gribbin
http://www.telegraph.co.uk/culture/books/bookreviews/9188438/ErwinSchro... 
Strange Beauty: Murray GellMann and the Revolution in TwentiethCentury Physics by George Johnson
http://www.goodreads.com/book/show/258459.Strange_Beauty 
Quantum by Manjit Kumar
http://www.guardian.co.uk/books/2008/nov/15/quantumphysicseinsteinboh... 
Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos by Seth Lloyd
https://www.nytimes.com/2006/04/02/books/review/welcometothemachine.html 
How to Teach Quantum Physics to Your Dog by Chad Orzel
http://www.timeshighereducation.co.uk/story.asp?storycode=413835 
Knocking on Heaven’s Door by Lisa Randall
https://www.goodreads.com/book/show/11297438knockingonheavensdoor 
Quantum Physics – A first Encounter by Valerio Scarani
http://www.goodreads.com/book/show/100028.Quantum_Physics 
Decoding Reality by Vlatko Vedral
https://www.goodreads.com/book/show/6739077decodingreality