ZEN TASK

DATA TYPES   PRIMITIVE               IMMUTABLE NON PRIMITIVE      MUTABLE COMPOSITE            COMBINATION OF PRIMITIVE & OTHER DATA TYPES TRIVIAL                    PRE DEFINED VALUES   JS DATA TYPES   Java script data types are classified into following three types 1.       PRIMITIVE                NUMBER, STRING, BOOLEAN 2.       TRIVIAL                    NULL, UNDEFINED 3.       COMPOSITE            OBJECT, ARRAY Number Integer, Float, NaN String ...

Why are Objects copied & compared by reference? Objects are copied and compared by reference because if objects are copied   by the value , it takes a lot of time and space to avoid those Objects copied & compared by reference

WINDOW vs SCREEN vs DOCUMENT         When JavaScript is executed inside the browser, the window object is the JavaScript Global object.   Screen and document are property of the window object.           When an HTML document is loaded into a web browser , it becomes a document object. It is the root node of the HTML document. The document actually gets loaded inside the window object and has properties available to it like title, URL, cookie, etc.           Screen is a small information object about physical screen dimensions . It can be used to display screen width, height, colour-depth, pixel-depth etc.