In Scripting languages like (JavaScript and old PHP versions) we use existing fundamental functions and method for performing our job.
Lets take an example in JavaScript we can use ajax or web-sockets only if they are supported by browser or methods exist or them in browser. But in languages like C or C++ , Java we can write that feature from scratch even if any library for that feature is not available but we can't do so in JavaScript.
can you support web-sockets in Internet Explorer 8 or prior with the help of JavaScript But you can write a plugin in C or C++ or Java which may add a feature of web-socket to Internet Explorer 8.
Basically in Scripting languages we write a code in a sequence which execute existing methods in a sequence to complete our job. Entering numbers and formula in a digital calculator to do a operation is also a very example of scripting language.We should note that the compiler/run-time-environment of every scripting language is always written in programming language in which we can add more features and methods and can write new libraries.
PHP This is language which is somewhat b/w programming and scripting. We can add new methods by adding compiled extensions written in another High Level Language. We can't add high level features of networking or creating image processing libraries directly in PHP.
P.S. I am really sorry for revolving my answer around PHP JavaScript only but I use these two because I have a considerable experience in these two.