Interpretor vs compiler - compiler checks once the sytax for the program if we add any new line then only that line would be compiled (check for sytax)

Every browser has a interpreter which will check the sytax for each line.

Java is interpreted by the browser. But brower has different engine.

Compiler for javascript is NodeJS. Before NodeJS

MEAN - MongoDB Express Angular Node

Servers

1. OS

Client SErver

Server

2. WebServices

Apache Tomcat

3. Database Server

Value Type and Reference type

Value Type /Primitive types is stored in STack and reference type is stored in heap.

var a=5, here var will have the data type as per the value in variable a hence we did not have to specify the data type

reference and primitive in Stack and object in heap.

Object obj = new Object();

here object is store in heap and obj(its reference ) is stored in stack