I'm a bit surprised that you put PHP in that list. My current workload is in it, and a relatively modern version of it, so maybe that surprise will turn around soon, but I've always felt that PHP was more obnoxious than even C to read and write.

Granted, I started out on LISP. My version of "easy to read and write" might be slightly masochistic. But I love Perl and Python and Javascript are definitely "you can jump in and get shit done if you have worked in most languages. It might not be idiomatic, but it'll work"...

PHP is easy to get into because of the simple (and tolerant) syntax and extremely simple static typing system. The weak typing also means it's easier for beginners.

It does require twice the lines of PHP code to make a Ruby or Python program equivalent, or more if you add phpdoc and static types though, so it is easier to read/write Ruby or Python, but only after learning the details of the language. Ruby's syntax is very expressive but very complex if you don't know it by heart.