I recently read about Shamir's Secret Sharing Scheme, created by Adi Shamir, one of the creators of RSA. I've been fascinated by its elegance and simplicity.
I write JavaScript for my day job, but I only recently started learning how engines optimize it. I had a ton of fun reading this article: https://mathiasbynens.be/notes/shapes-ics (which I discovered in another HN post somewhere)
The fundamentals of Information Theory via (the late) David Mackay's lectures and textbook (homepage with links to the videos and free online textbook here: http://www.inference.org.uk/itprnn/).
An amazing Python library built atop Keras and Tensorflow for composing and training probabilistic models in just a few lines. If you're interested in machine learning and/or Bayesian statistics and modeling, you owe it to yourself to check this library out. The webpage has several different tutorials that are all super interesting.
I don't know too much, but I believe this library will be superseded by Tensorflow Probability (Dustin Tran, who writes & maintains Edward is also on the TF Probability team).
Either one of these are super super valuable if you're looking to play around with and invent new ML algorithms, since you can do in 5 lines what would have taken you 1,000 lines and 4 days of debugging to do without these libraries.
When creating spacial geography point in sql server, the longitude comes first (lng, lat). I always thought it would be latitude then longitude.
Interestingly, some points that I've inserted passed the validation, but later I realized the values were swapped when I tried to query nearest neighbor and the points were no where near.
That hedge funds use something called twisted light to get speed advantages on the network stack to the exchange. This essentially lets them change orders (via bit flipping) when they are already on the wire making their way to the matching engine.
FSMs are amazing, and are the one thing I learned from a programming book. I could not resist teaching it to an interviewer during a coding challenge... don't they cover FSMs in code camps?
Idris and dependent types via Type-Driven Development. It's an excellent book, very clearly written and approachable. May be a bit more challenging if you haven't used Haskell/SML/OCaml or similar languages before.
https://en.wikipedia.org/wiki/Shamir%27s_Secret_Sharing