Javascript is a dynamic computer programming language, most commonly used as part of web browsers, whose implementations allow client-side scripts to interact with the user, control the browser, communicate asynchronously, and alter the document content that is displayed.
SharePoint extensively uses JavaScript, to work with data and user interfaces. JavaScript is heavily used in all versions of SharePoint and makes up over 70% of a page load, also JavaScript in SharePoint is becoming more integral, especially from version 15. (SharePoint 2013). With Apps becoming mainstream, we will see an ever increasing rise in the requirement of JavaScript for SharePoint.
You can find the detailed javascript documentation, here.
Questions having the tag javascript regard all aspects of JavaScript in SharePoint and Apps, under all SharePoint SKUs.
