Hide or show list form fields in SharePoint using jQuery

David Lozzi has written a jquery library which is useful our daily development activites.
http://davidlozzi.com/2014/01/14/sharepoint-2013-script-hide-or-disable-your-fields
ExecuteOrDelayUntilScriptLoaded(function(){

  Lozzi.Fields.disableWithAllowance("Employee Name",["LeaveEntryAuthorization"]);

  },"sp.js");

sp.js should load before execute the code.