JavaScript From Scratch ( Part 1 - Beginner Level)

Install and set up VSCode as your JavaScript editor, create a project folder, and use the live server extension to view HTML changes instantly in the browser.

Create your first JavaScript program in an HTML file, learn script placement in head or body, and link external files like assets/js/main.js using script src and console.log for debugging.

Learn how to display information in JavaScript using alert, console.log, document.write, and innerHTML, including accessing the window object and manipulating elements by id.

Learn how JavaScript treats variables as containers for data, declare them with var, let, or const, assign values with =, follow naming rules, and view results in the browser console.

Learn how to declare and assign JavaScript variables with var and let, inspect undefined values via console.log, and understand redeclaration rules for var versus let with numbers and strings.

learn how const defines a constant reference to a value, must be assigned on declaration, cannot be redeclared or reassigned, and used for arrays, objects, functions, and regex in JavaScript.

Explore JavaScript data types, including numbers, strings, booleans, undefined, null, symbol, and objects, and learn how variables can change types at runtime with dynamic typing.

Explore arrays in JavaScript, including creating arrays with square brackets or the Array constructor, using var, let, or const, accessing elements by zero-based indices, and checking the array length.

Define arrays in JavaScript with const; the array can’t be reassigned, but items can change, and note that the last element is accessed via length minus one with zero-based indexing.

Define and use objects in JavaScript to group properties like email, name, age, and gender with curly braces, the new keyword, or an object constructor.

Explore how to create empty objects in JavaScript, define properties with dot notation or brackets, and assign values, including nested objects and arrays of objects.

Discover how JavaScript functions encapsulate a task as a reusable code block, defined with a name and parameters and invoked with arguments to add numbers.

Define a JavaScript function using the function keyword with two parameters x and y to add numbers and log the result to the console.

Learn how to return values from JavaScript functions and exit on a return statement. Use the returned result in the calling code, for example with numbers, arrays, and objects.

Set default values for function parameters in JavaScript using the assignment operator. See how the sum example uses zero defaults to prevent undefined results when arguments are missing.

Variables defined inside a function have function scope and cannot be accessed outside; parameters act as variables, call with parentheses to obtain result and avoid errors: x is not defined.

Explore how to use JavaScript array methods, focusing on shift to remove the first element, update indices, and log results, with live experiments on arrays of mixed types.

Learn array manipulation with unshift and shift to modify the beginning, and pop and push to alter the end, observing how length updates after each operation.

Copy an array with slice to create a new array. Use splice to remove or insert items at a start index, with a delete count and new values.

Demonstrate array search and conversion techniques using indexOf, lastIndexOf, and includes to locate items, and toString and join to convert arrays into strings with default or custom separators.

Discover how to use the JavaScript forEach method to run a function for every array item, accessing value, index, and the array itself.

Learn how the map method transforms arrays by returning a new array, and compare it to forEach, which does not return a new array.

Discover how to use arithmetic operators in JavaScript to perform addition, subtraction, multiplication, division, modulus, and exponentiation on literals and variables, and understand precedence and prefix or postfix forms.

Explains how assignment operators work in JavaScript, showing arithmetic operations and the shorthand forms like +=, -=, *=, /=, %=, and **= to update numbers.

Explore comparison and logical operators in JavaScript, showing how == vs === perform equality checks based on value and type, and how numbers, strings, empty strings, and NaN affect results.

Explore JavaScript comparison and logical operators, including greater than, less than, greater than or equal to, less than or equal to, not, and, or, and their results in conditionals.

Explore core conditional statements in JavaScript from scratch, including if, else, else if, and switch. Use logical operators and the ternary operator to evaluate conditions.

Learn to use switch statements to map a date month index (0–11) to month names, with cases, breaks, and a default, demonstrated via console.log output.

Explore how switch statements select code blocks based on an expression, using break, default, and grouped cases to map month numbers to seasons, with strict comparison.

Learn how to use loops in JavaScript to execute code repeatedly, including for, for in, while, and do while, with for loop's three expressions and array usage.

Learn how to implement nested for loops in JavaScript to generate a 10 by 10 multiplication table, control flow with break and continue, and calculate a factorial.

Compare while and do while loops in JavaScript, showing how conditions control execution and why do while runs at least once while while may not run; discuss counter use.

Explore for-in and for-of loops in JavaScript, learn syntax for object keys and array items, iterate over arrays and strings, and understand how to access values and differences.