Course Content
Data types and Values
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Object-oriented programming in JavaScript
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Error handling and debugging in JavaScript
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JavaScript functions for string and array manipulation
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JavaScript Libraries and Frameworks
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JavaScript
About Lesson

Statements

A statement is a group of words, numbers, and operators that perform a specific task. It is a fundamental unit of code that performs a specific action or task. It is the building block of a program, and a sequence of statements forms the instructions that a computer follows to execute a program. Each statement instructs the computer to perform a specific operation, make a decision, or manipulate data.

 

In JavaScript:
statements are instructions for the computer to perform specific actions.
For instance, the statement a = b * 7; involves variables: a and b.
Variables act like boxes to store data, and they hold values, such as the number 15, used by the program. Variables are placeholders representing actual values.
The value 7 in the statement is a literal value; This is because it isn’t stored in a variable.

 

Additionally, the characters = and * are operators. Operators perform actions involving values and variables, like assignment and mathematical multiplication. Most JavaScript statements end with a semicolon ;.

 

The statement a = b * 7; instructs the computer to retrieve the current value from variable b, multiply it by 7, and then save the outcome into a different variable called a.

 

Here are key points to understand about statements in coding:

# Key Point Description
1 Basic Instruction A statement is a basic unit of code that provides instructions for a specific action or task. It is the building block of a program.
2 Termination Statements are usually terminated with a semicolon (;) in languages like JavaScript, C++, and Java. The semicolon marks the end of a statement and separates multiple statements.
3 Examples Common types of statements include variable declarations, assignments, function calls, loops, and conditionals. These statements instruct the computer to perform specific operations.
4 Sequence Programs are executed sequentially, following the order of statements in the code. The computer processes statements one by one unless control structures alter the sequence.
5 Control Flow Statements control the flow of execution. Conditional statements (if, switch) enable different actions based on conditions, and loops (for, while) allow repetition of statements.
6 Functionality Statements can be simple or complex. A single statement might involve assigning a value, while complex statements could include loops that perform multiple operations.
7 Code Blocks Some statements define code blocks enclosed in curly braces {}. Code blocks group multiple statements and create a scope for variable declarations.
8 Syntax and Grammar Statements must follow the syntax and grammar rules of the programming language. Incorrect syntax can lead to errors during compilation or runtime.
9 Example Example: In JavaScript, let greeting = "Hello, world!"; is a statement that declares a variable and assigns a value.
10 Statement vs. Expression Statements perform actions, while expressions produce results. Statements don’t necessarily return values, whereas expressions do.
11 Error Detection Error Detection: Syntax errors, logical errors, and runtime errors can occur in statements. Debugging tools help identify and correct these issues.
12 Comments Adding comments within statements can help document code and enhance its readability.

 

Overall, statements are essential components of programming languages that allow programmers to provide instructions to computers in a structured and understandable way. By combining statements in various ways, developers create powerful and functional programs.