The “this keyword” in Java refer to the the current object (current instance). All your instance variables may be referred as 'this.variableName' even though it is implicit in most cases. 

The “this keyword”  is mostly useful in below cases:

1. Refer to instance variables of a class when a local variable has precedence over it.

Java is a programming language that follows the Object-Oriented Programming (OOP) principles. OOP model focusses on realworld objects to model applications. A real world object will have some properties and some behaviour. For example, human object will have properties like height, weight etc. and behaviours like walk, run, talk, etc.  

Looping constructs in Java are:

• For statement

• For-each statement

• While statement

• Do while statement

We will see for and for-each here. We will see while, do while, break and continue statements in next note. 

The for statement

Syntax of for loop is:

Decision control statements can change the execution flow of a program. 

Decision control statements in Java are:

• if statement

• Conditional operator

• switch statement

Literals are numbers, characters, and string representations in your program. Literals can be classified as numeric literals, character literals and string literals.