SharePoint 2013 get current user using JavaScript

Question

How to get current user name using JavaScript in Script Editor web part?

Answer 1

I had to do it using XML, put the following in a Content Editor Web Part by adding a Content Editor Web Part, Edit the Web Part, then click the Edit Source button and paste in this:

Check the following link to see if your data is XML or JSON:

https:///_api/web/currentuser

In the accepted answer Kate uses this method:

var userid= _spPageContextInfo.userId;
var requestUri = _spPageContextInfo.webAbsoluteUrl + "/_api/web/getuserbyid(" + userid + ")