What does TL;DR mean?

I’ve used the letters TL;DR to denote the quick 15 second summary of a post.

The letters TL;DR are an editor’s notation to a writer that the following text is “too long; didn’t read”.

As an engineer, I am detail oriented and consequently I provide too much detail for most people – which means I constantly run into “TL;DR” when I look at my own work.