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NCVirtual Coding Club Course
Introduction
Responsive Web Design
Basic HTML and HTML5
Say Hello to HTML Elements
Headline with the h2 Element
Inform with the Paragraph Element
Fill in the Blank with Placeholder Text
Uncomment HTML
Comment out HTML
Delete HTML Elements
Introduction to HTML5 Elements
Add Images to Your Website
Link to External Pages with Anchor Elements
Link to Internal Sections of a Page with Anchor Elements
Nest an Anchor Element within a Paragraph
Make Dead Links Using the Hash Symbol
Turn an Image into a Link
Create a Bulleted Unordered List
Create an Ordered List
Create a Text Field
Add Placeholder Text to a Text Field
Create a Form Element
Add a Submit Button to a Form
Use HTML5 to Require a Field
Create a Set of Radio Buttons
Create a Set of Checkboxes
Use the value attribute with Radio Buttons and Checkboxes
Check Radio Buttons and Checkboxes by Default
Nest Many Elements within a Single div Element
Define the Head and Body of an HTML Document
Declare the Doctype of an HTML Document
Basic CSS
Change the Color of Text
Use CSS Selectors to Style Elements
Use a CSS Class to Style an Element
Style Multiple Elements with a CSS Class
Change the Font Size of an Element
Set the Font Family of an Element
Import a Google Font
Specify How Fonts Should Degrade
Size Your Images
Add Borders Around Your Elements
Add Rounded Corners with border-radius
Make Circular Images with a border-radius
Give a Background Color to a div Element
Set the id of an Element
Use an id Attribute to Style an Element
Adjust the Padding of an Element
Adjust the Margin of an Element
Add a Negative Margin to an Element
Add Different Padding to Each Side of an Element
Add Different Margins to Each Side of an Element
Use Clockwise Notation to Specify the Padding of an Element
Use Clockwise Notation to Specify the Margin of an Element
Use Attribute Selectors to Style Elements
Understand Absolute versus Relative Units
Style the HTML Body Element
Inherit Styles from the Body Element
Prioritize One Style Over Another
Override Styles in Subsequent CSS
Override Class Declarations with Inline Styles
Override Class Declarations with Inline Styles
Override All Other Styles by using Important
Use Hex Code for Specific Colors
Use Hex Code to Mix Colors
Use Abbreviated Hex Code
Use RGB values to Color Elements
Use RGB to Mix Colors
Use CSS Variables to change several elements at once
Create a custom CSS Variable
Use a custom CSS Variable
Attach a Fallback value to a CSS Variable
Improve Compatibility with Browser Fallbacks
Inherit CSS Variables
Change a variable for a specific area
Use a media query to change a variable
Applied Visual Design
Create Visual Balance Using the text-align Property
Adjust the Width of an Element Using the width Property
Adjust the Height of an Element Using the height Property
Use the strong Tag to Make Text Bold
Use the u Tag to Underline Text
Use the em Tag to Italicize Text
Use the s Tag to Strikethrough Text
Create a Horizontal Line Using the hr Element
Adjust the background-color Property of Text
Adjust the Size of a Header Versus a Paragraph Tag
Add a box-shadow to a Card-like Element
Decrease the Opacity of an Element
Use the text-transform Property to Make Text Uppercase
Set the font-size for Multiple Heading Elements
Set the font-weight for Multiple Heading Elements
Set the font-size of Paragraph Text
Set the line-height of Paragraphs
Adjust the Hover State of an Anchor Tag
Change an Element's Relative Position
Move a Relatively Positioned Element with CSS Offsets
Lock an Element to its Parent with Absolute Positioning
Lock an Element to the Browser Window with Fixed Positioning
Push Elements Left or Right with the float Property
Change the Position of Overlapping Elements with the z-index Property
Center an Element Horizontally Using the margin Property
Learn about Complementary Colors
Learn about Tertiary Colors
Adjust the Color of Various Elements to Complementary Colors
Adjust the Hue of a Color
Adjust the Tone of a Color
Create a Gradual CSS Linear Gradient
Use a CSS Linear Gradient to Create a Striped Element
Create Texture by Adding a Subtle Pattern as a Background Image
Use the CSS Transform scale Property to Change the Size of an Element
Use the CSS Transform scale Property to Scale an Element on Hover
Use the CSS Transform Property skewX to Skew an Element Along the X-Axis
Use the CSS Transform Property skewY to Skew an Element Along the Y-Axis
Create a Graphic Using CSS
Create a More Complex Shape Using CSS and HTML
Learn How the CSS @keyframes and animation Properties Work
Use CSS Animation to Change the Hover State of a Button
Modify Fill Mode of an Animation
Create Movement Using CSS Animation
Create Visual Direction by Fading an Element from Left to Right
$$$
Make a CSS Heartbeat using an Infinite Animation Count
Animate Elements at Variable Rates
Animate Multiple Elements at Variable Rates
Change Animation Timing with Keywords
Learn How Bezier Curves Work
Use a Bezier Curve to Move a Graphic
Make Motion More Natural Using a Bezier Curve
Applied Accessibility
Add a Text Alternative to Images for Visually Impaired Accessibility
Know When Alt Text Should be Left Blank
Use Headings to Show Hierarchical Relationships of Content
Jump Straight to the Content Using the main Element
Wrap Content in the article Element
Make Screen Reader Navigation Easier with the header Landmark
Make Screen Reader Navigation Easier with the nav Landmark
Make Screen Reader Navigation Easier with the footer Landmark
Improve Accessibility of Audio Content with the audio Element
Improve Chart Accessibility with the figure Element
Improve Form Field Accessibility with the label Element
Wrap Radio Buttons in a fieldset Element for Better Accessibility
Add an Accessible Date Picker
Standardize Times with the HTML5 datetime Attribute
Make Elements Only Visible to a Screen Reader by Using Custom CSS
Improve Readability with High Contrast Text
Avoid Colorblindness Issues by Using Sufficient Contrast
Avoid Colorblindness Issues by Carefully Choosing Colors that Convey Information
Give Links Meaning by Using Descriptive Link Text
Make Links Navigable with HTML Access Keys
Use tabindex to Add Keyboard Focus to an Element
Use tabindex to Specify the Order of Keyboard Focus for Several Elements
Responsive Web Design Principles
Create a Media Query
Make an Image Responsive
Use a Retina Image for Higher Resolution Displays
Make Typography Responsive
CSS Flexbox
Use display: flex to Position Two Boxes
Add Flex Superpowers to the Tweet Embed
Use the flex-direction Property to Make a Row
Apply the flex-direction Property to Create Rows in the Tweet Embed
Use the flex-direction Property to Make a Column
Apply the flex-direction Property to Create a Column in the Tweet Embed
Align Elements Using the justify-content Property
Use the justify-content Property in the Tweet Embed
Align Elements Using the align-items Property
Use the align-items Property in the Tweet Embed
Use the flex-wrap Property to Wrap a Row or Column
Use the flex-shrink Property to Shrink Items
Use the flex-grow Property to Expand Items
Use the flex-basis Property to Set the Initial Size of an Item
Use the flex Shorthand Property
Use the order Property to Rearrange Items
Use the align-self Property
CSS Grid
Create Your First CSS Grid
Add Columns with grid-template-columns
Add Rows with grid-template-rows
Use CSS Grid units to Change the Size of Columns and Rows
Create a Column Gap Using grid-column-gap
Create a Row Gap using grid-row-gap
Add Gaps Faster with grid-gap
Use grid-column to Control Spacing
Use grid-row to Control Spacing
Align an Item Horizontally using justify-self
Align an Item Vertically using align-self
Align All Items Horizontally using justify-items
Align All Items Vertically using align-items
Divide the Grid Into an Area Template
Place Items in Grid Areas Using the grid-area Property
Use grid-area Without Creating an Areas Template
Reduce Repetition Using the repeat Function
Limit Item Size Using the minmax Function
Create Flexible Layouts Using auto-fill
Create Flexible Layouts Using auto-fit
Use Media Queries to Create Responsive Layouts
Create Grids within Grids
JavaScript Algorithms and Data Structures
Basic JavaScript
Comment Your JavaScript Code
Declare JavaScript Variables
Storing Values with the Assignment Operator
Assigning the Value of One Variable to Another
Initializing Variables with the Assignment Operator
Understanding Uninitialized Variables
Understanding Case Sensitivity in Variables
Add Two Numbers with JavaScript
Subtract One Number from Another with JavaScript
Multiply Two Numbers with JavaScript
Divide One Number by Another with JavaScript
Increment a Number with JavaScript
Decrement a Number with JavaScript
Create Decimal Numbers with JavaScript
Multiply Two Decimals with JavaScript
Divide One Decimal by Another with JavaScript
Finding a Remainder in JavaScript
Compound Assignment With Augmented Addition
Compound Assignment With Augmented Subtraction
Compound Assignment With Augmented Multiplication
Compound Assignment With Augmented Division
Declare String Variables
Escaping Literal Quotes in Strings
Quoting Strings with Single Quotes
Escape Sequences in Strings
Concatenating Strings with Plus Operator
Concatenating Strings with the Plus Equals Operator
Constructing Strings with Variables
Appending Variables to Strings
Find the Length of a String
Use Bracket Notation to Find the First Character in a String
Understand String Immutability
Use Bracket Notation to Find the Nth Character in a String
Use Bracket Notation to Find the Last Character in a String
Use Bracket Notation to Find the Nth-to-Last Character in a String
Word Blanks
Store Multiple Values in one Variable using JavaScript Arrays
Nest one Array within Another Array
Access Array Data with Indexes
Modify Array Data With Indexes
Access Multi-Dimensional Arrays With Indexes
Manipulate Arrays With push()
Manipulate Arrays With pop()
Manipulate Arrays With shift()
Manipulate Arrays With unshift()
Shopping List
Write Reusable JavaScript with Functions
Passing Values to Functions with Arguments
Global Scope and Functions
Local Scope and Functions
Global vs. Local Scope in Functions
Return a Value from a Function with Return
Understanding Undefined Value returned from a Function
Assignment with a Returned Value
Stand in Line
Understanding Boolean Values
Use Conditional Logic with If Statements
Comparison with the Equality Operator
Comparison with the Strict Equality Operator
Practice comparing different values
Comparison with the Inequality Operator
Comparison with the Strict Inequality Operator
Comparison with the Greater Than Operator
Comparison with the Greater Than Or Equal To Operator
Comparison with the Less Than Operator
Comparison with the Less Than Or Equal To Operator
Comparisons with the Logical And Operator
Comparisons with the Logical Or Operator
Introducing Else Statements
Introducing Else If Statements
Logical Order in If Else Statements
Chaining If Else Statements
Golf Code
Selecting from Many Options with Switch Statements
Adding a Default Option in Switch Statements
Multiple Identical Options in Switch Statements
Replacing If Else Chains with Switch
Returning Boolean Values from Functions
Return Early Pattern for Functions
Counting Cards
Build JavaScript Objects
Accessing Object Properties with Dot Notation
Accessing Object Properties with Bracket Notation
Accessing Object Properties with Variables
Updating Object Properties
Add New Properties to a JavaScript Object
Delete Properties from a JavaScript Object
Using Objects for Lookups
Testing Objects for Properties
Manipulating Complex Objects
Accessing Nested Objects
Accessing Nested Arrays
Record Collection
Iterate with JavaScript While Loops
Iterate with JavaScript For Loops
Iterate Odd Numbers With a For Loop
Count Backwards With a For Loop
Iterate Through an Array with a For Loop
Nesting For Loops
Iterate with JavaScript Do...While Loops
Replace Loops using Recursion
Profile Lookup
Generate Random Fractions with JavaScript
Generate Random Whole Numbers with JavaScript
Generate Random Whole Numbers within a Range
Use the parseInt Function
Use the parseInt Function with a Radix
Use the Conditional (Ternary) Operator
Use Multiple Conditional (Ternary) Operators
Use Recursion to Create a Countdown
Use Recursion to Create a Range of Numbers
ES6
Explore Differences Between the var and let Keywords
Compare Scopes of the var and let Keywords
Declare a Read-Only Variable with the const Keyword
Mutate an Array Declared with const
Prevent Object Mutation
Use Arrow Functions to Write Concise Anonymous Functions
Write Arrow Functions with Parameters
Set Default Parameters for Your Functions
Use the Rest Parameter with Function Parameters
Use the Spread Operator to Evaluate Arrays In-Place
Use Destructuring Assignment to Extract Values from Objects
Use Destructuring Assignment to Assign Variables from Objects
Use Destructuring Assignment to Assign Variables from Nested Objects
Use Destructuring Assignment to Assign Variables from Arrays
Use Destructuring Assignment with the Rest Parameter to Reassign Array Elements
Use Destructuring Assignment to Pass an Object as a Function's Parameters
Create Strings using Template Literals
Write Concise Object Literal Declarations Using Object Property Shorthand
Write Concise Declarative Functions with ES6
Use class Syntax to Define a Constructor Function
Use getters and setters to Control Access to an Object
Create a Module Script
Use export to Share a Code Block
Reuse JavaScript Code Using import
Use * to Import Everything from a File
Create an Export Fallback with export default
Import a Default Export
Create a JavaScript Promise
Complete a Promise with resolve and reject
Handle a Fulfilled Promise with then
Handle a Rejected Promise with catch
Regular Expressions
Using the Test Method
Match Literal Strings
Match a Literal String with Different Possibilities
Ignore Case While Matching
Extract Matches
Find More Than the First Match
Match Anything with Wildcard Period
Match Single Character with Multiple Possibilities
Match Letters of the Alphabet
Match Numbers and Letters of the Alphabet
Match Single Characters Not Specified
Match Characters that Occur One or More Times
Match Characters that Occur Zero or More Times
Find Characters with Lazy Matching
Find One or More Criminals in a Hunt
Match Beginning String Patterns
Match Ending String Patterns
Match All Letters and Numbers
Match Everything But Letters and Numbers
Match All Numbers
Match All Non-Numbers
Restrict Possible Usernames
Match Whitespace
Match Non-Whitespace Characters
Specify Upper and Lower Number of Matches
Specify Only the Lower Number of Matches
Specify Exact Number of Matches
Check for All or None
Positive and Negative Lookahead
Check For Mixed Grouping of Characters
Reuse Patterns Using Capture Groups
Use Capture Groups to Search and Replace
Remove Whitespace from Start and End
Debugging
Use the JavaScript Console to Check the Value of a Variable
Understanding the Differences between the freeCodeCamp and Browser Console
Use typeof to Check the Type of a Variable
Catch Misspelled Variable and Function Names
Catch Unclosed Parentheses, Brackets, Braces and Quotes
Catch Mixed Usage of Single and Double Quotes
Catch Use of Assignment Operator Instead of Equality Operator
Catch Missing Open and Closing Parenthesis After a Function Call
Catch Arguments Passed in the Wrong Order When Calling a Function
Catch Off By One Errors When Using Indexing
Use Caution When Reinitializing Variables Inside a Loop
Prevent Infinite Loops with a Valid Terminal Condition
Basic Data Structures
Use an Array to Store a Collection of Data
Access an Array's Contents Using Bracket Notation
Add Items to an Array with push() and unshift()
Remove Items from an Array with pop() and shift()
Remove Items Using splice()
Add Items Using splice()
Copy Array Items Using slice()
Copy an Array with the Spread Operator
Combine Arrays with the Spread Operator
Check For The Presence of an Element With indexOf()
Iterate Through All an Array's Items Using For Loops
Create complex multi-dimensional arrays
Add Key-Value Pairs to JavaScript Objects
Modify an Object Nested Within an Object
Access Property Names with Bracket Notation
Use the delete Keyword to Remove Object Properties
Check if an Object has a Property
Iterate Through the Keys of an Object with a for...in Statement
Generate an Array of All Object Keys with Object.keys()
Modify an Array Stored in an Object
Front End Development Libraries
Data Visualization
APIs and Microservices
Quality Assurance
Scientific Computing with Python
Data Analysis with Python
Information Security
Machine Learning with Python
Coding Interview Prep
JavaScript Algorithms and Data Structures
Basic JavaScript
Subtract One Number from Another with JavaScript
Subtract One Number from Another with JavaScript
Summary
JavaScript uses the
-
symbol for subtraction.
Final Code
var
difference
=
45
-
33
;