StopWord.js provides funtionalities to remove stop words (English) from a String object. 

Example -

testString = "This is a cat";
testString = testString.removeStopWords(); // returns "cat"

testString = "I was looking for a way to schedule simple jobs in Ruby on Rails. I figured out BackgrounDRB is quite a promising job server and scheduler. But it’s implementation and installation is not as simple as i was looking for. If you need some advance job scheduling i will recommend you to look in to BackgrounDRB.";
testString = testString.removeStopWords(); // returns "schedule simple jobs Ruby Rails figured BackgrounDRB promising job server scheduler implementation installation simple advance job scheduling will recommend BackgrounDRB"

You can also check if a string is a stop word by following function

stopWord = String.isStopWord("this"); //returns true 
stopWord = String.isStopWord("cat"); //returns false

I have used Long Stopword List from http://www.ranks.nl/resources/stopwords.html.