
1- Headings : HTML has six “levels” of headings from h1 to h6
2- Paragraphs : To create a paragraph, surround the words that make up the paragraph with an opening < p > tag and closing < /p > tag
3- Bold & Italic : Line Breaks & Horizontal Rules
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CSS treats each HTML element as if it appears inside its own box and uses rules to indicate how that element should look.
Rules are made up of selectors (that specify the elements the rule applies to) and declarations (that indicate what these elements should look like).
Different types of selectors allow you to target your rules at different elements.
Declarations are made up of two parts: the properties of the element that you want to change, and the values of those properties. For example, the font-family property sets the choice of font, and the value arial specifies Arial as the preferred typeface.
CSS rules usually appear in a separate document, although they may appear within an HTML page
A script is made up of a series of statements. Each statement is like a step in a recipe.
Scripts contain very precise instructions. For example, you might specify that a value must be remembered before creating a calculation using that value.
Variables are used to temporarily store pieces of information used in the script.
Arrays are special types of variables that store more than one piece of related information.
JavaScript distinguishes between numbers (0-9), strings (text), and Boolean values (true or false).
Expressions evaluate into a single value.
Expressions rely on operators to calculate a value.
Conditional statements allow your code to make decisions about what to do next.
Comparison operators (===, ! ==, ==, ! =, <, >, <=, =>) are used to compare two operands.
Logical operators allow you to combine more than one set of comparison operators.
if … else statements allow you to run one set of code if a condition is true, and another if it is false.
switch statements allow you to compare a value against possible outcomes (and also provides a default option if none match).