On the Mayflower blog there's a new post talking about some of the common pitfalls for PHP developers that are starting their work with the front end Javascript language.

If we take a look at our current job advertisement, these knowledge is still important, but also skills in JavaScript are asked and strongly desired. If you wonder why JavaScript is so popular at these times, my answer is quite simple: The browser is no longer a stupid instrument to view some static websites on the internet- the browser turned into an (Web-) Application Platform that provides more content then plain text.

They start by comparing some of the data types common between the two (with most things on the Javascript side ending up as an object). They also talk about the fact that arrays are not (technically) arrays like PHP developers think of them. They finish it off with two more common problems PHP devs have when making the move - looping through arrays and "the thing with the semicolon".