Here's our writeup on spaced repetition, a learning and memory technique widely used by language learners and med students. It works for much more than those topics, though! (Execute Program is the first spaced repetition system dedicated to programming.)

RT @exec_prog: Black Friday sale: 40% off the first 12 months of an individual subscription!. And a new course: Python in Detail. 563 inter….

Black Friday sale: 40% off the first 12 months of an individual subscription!. And a new course: Python in Detail. 563 interactive code examples in 44 lessons, covering Python's dunder methods, object system, iterators, generators, and many more topics.

RT @exec_prog: Our Black Friday sale starts now: 40% off for the first 12 months of any individual subscription!. We also have a new course….

Our Black Friday sale starts now: 40% off for the first 12 months of any individual subscription!. We also have a new course, "Python for Programmers." 701 interactive code examples in 55 lessons, covering the core of the Python language.

RT @garybernhardt: The @exec_prog "Python for Programmers" course is in open beta! It'll be about a week long, during which the course is f….

If you have education budget expiring at the end of the year, we humbly suggest Execute Program's courses on TypeScript and other programming languages!

Today is your last chance to get our Black Friday discount: 40% off the first year for individual subscriptions! Learn TypeScript from Basics to Advanced, with interactive code examples the whole way. (Other languages and tools too!)

Black Friday sale: 40% off the first year for individual subscriptions, paid monthly or yearly! Our highly interactive courses cover TypeScript, Regular Expressions, Modern JavaScript, JavaScript Concurrency, SQL, and JavaScript Arrays.

Execute Program's Black Friday sale starts today! 40% off the first year for individual subscriptions (paid monthly or yearly). Eight programming language courses with 2,241 interactive code examples, including TypeScript courses from Basics to Advanced.

Totally appropriate response!

Blog post: "TypeScript Features to Avoid". As with any mature language, we have to make difficult decisions about which TypeScript features to use and which to avoid. Based on our experience, here are four recommendations about which features to avoid.

We now have three TypeScript courses: Basics, Everyday, and Advanced. They span a wide range of experience levels: there's something for a static type beginner and for daily TS users. Here's a topic summary. Subscriptions are still 40% off until tomorrow!

Execute Program's Black Friday sale is still on! 40% off the first year for individual subscriptions (including the yearly option). Eight highly interactive programming language courses, including the most comprehensive TypeScript courses available.

Execute Program is on sale through Nov 30! 40% off the first year for individual subscriptions (including the new yearly billing option). Eight highly interactive programming language courses, including the most comprehensive TypeScript courses available.

RT @getupleveled: Can't recommend @exec_prog enough! ❤️ Really amazing, the effort and attention to detail put in these learning materials!….

RT @eastouest: Seen on @exec_prog in a lesson on SQL join mistakes:

RT @TheYoctoJester: Just read on @exec_prog: "First, we have a Util namespace: the inevitable junk drawer that shows up in every applicatio….

If you want to give our array course a try, those two lesson links will work. But you'll have the best experience by going to and starting from the beginning. It covers all of the array methods, with 216 code examples, most of which are interactive.

As an illustration: Execute Program's reduce lesson ( is 860 words long. It's the longest lesson in our JavaScript array course. Our map lesson ( is only 139 words. (16% as many words!) It's one of the shortest. Huge difference.