Identifier An identifier is a name that identifies either a unique object or a unique class of objects, where the “object” or class may be an idea, physical [countable] object, or physical [noncountable] substance.
An identifier is a name you assign to a local variable, function parameter, function, function arguments, class, package/namespace, filename, etc.
The program code consists of statements that are made up of keywords, expressions, and operators.
The actions that a program takes are expressed in statements.
Common actions include
- Declaring variables // var firstOddNumber;
- Assigning values // firstOddNumber = 1;
- Declaration statements with initializers
equivalent to declaration statement followed by assignment statement:
- const double pi = 3.14159; // Declare and initialize constant.
- Calling methods
- Looping through collections
- Branching to one or another block of code, depending on a given condition.
- Expression statement (postfix increment). //counter++;
The order in which statements are executed in a program is called the flow of control or flow of execution. The flow of control may vary every time that a program is run, depending on how the program reacts to input that it receives at run time.
A statement can consist of a single line of code that ends in a semicolon, or a series of single-line statements in a block. A statement block is enclosed in {} brackets and can contain nested blocks.