HTML and CSS Basics

Introduction

HTML is the markup that contains all the actual stuff that a web page has. All the text on this page you’re reading right now lives inside HTML tags that tell your browser how to order the content on the page. Go on, right click any element on the page and choose “Inspect Element” to open up your browser’s Developer Tools and it will show you the structure of the page.

CSS tells the browser if you want to display any of those tags a particular way, for instance, turning its background blue and pushing it a little to the left. In your Developer Tools, you can see the CSS styles in another panel, usually showing which specific properties were inherited from which lines of CSS.

Learning Outcomes

Look through these now and then use them to test yourself after doing the assignment:

Why do we separate HTML and CSS?
What are classes and IDs (and how are they different)?
What are elements?
What are tags?
What are attributes?
What are forms?
What is a div?
What are selectors?
What are properties?
What are values?
What is the “query string” in a URL and what does it do?
What is the difference between “pixels” and “ems”?
How do CSS styles for a particular element get inherited? i.e. how does an element get its “default” styles?
What are two CSS attributes you can change to push an element around on the page?
What are the three different ways to include CSS in your project or use CSS to style a particular element?
What is the “default stylesheet” or “user agent stylesheet”?
Why use a CSS reset file?

Assignment

Dive right into learning HTML and CSS with freeCodeCamp’s interactive tutorials. Do the entire section labeled “Responsive Web Design Certification”. It’s long and if you’re new will take you at least a few days to get through but it will give you a really solid foundation to build on moving forward. They have some projects at the end. They’re good practice, but you can consider them optional. (A large part of their proposed ‘300 hours’ for completion comes from these projects.. it probably won’t take you that long)
Optional: Learn about your browser’s default stylesheet and CSS resets in this video (reset starting at the 2:00 mark). This is why there are some spaces that show up in your layout even if you haven’t specified CSS. Real developers almost always use a CSS reset to blow away the default stylesheet and let them work from scratch. If you’re still curious, here’s a longer video on resets.

Additional Resources

This section contains helpful links to other content. It isn’t required, so consider it supplemental for if you need to dive deeper into something.

You might it find it helpful to bookmark the Complete Guide to Flexbox and the Complete Guide to Grid from CSS Tricks. These are both excellent references that you’ll find handy as you start to apply CSS in projects.
Another good page to bookmark for later reference is Centering in CSS: A Complete Guide, also from CSS Tricks.
W3 Schools’ CSS tutorial
OverAPI’s HTML Cheat Sheet
OverAPI’s CSS Cheat Sheet
Learn CSS Layout

Web Development 101