A visual introduction to big O notation

Beautiful article but that's not what big O means. The author seems to be describing something that is usually called (upper case) Theta. Big O is an upper bound.

This “well ackchyually“ is not particularly helpful. You’re not wrong. But this argument was lost 30 years ago. The programming field has been using “Big O” loosely.

There's a comment thread further down that disagrees with you.

...where?

Ah, I conflated worst case with upper bound. My mistake.

I am not interested in arguing so I'll just repeat that your article is beautiful and even though it's not entirely correct I think it has value and I appreciate the time you spent working on this and putting it out to help others.

Thank you, I appreciate that a lot.

I've had conversations at work where the difference was important. Mass adoption of quicksort implies I'm not the only one.