The main agents in the process of using the web are:
The user opens a web browser. The user commands the browser to do something and the browser sends a signal over the internet ('the world's largest computer network'). HTTP, an applications protocol, takes the signals and sends them to servers that host the content. The servers then send information back along the chain of command (through HTTP through the internet through my browser) back to me, the user.
HTML is the main type of document on the web that glues the internet together. This type of document contains:
The distinction between HTML tags, elements, and attributes was murky for me at first. Luckily, this resource from 456 Berea Street provided some clarity. In summary:
There are two varieties of elements: inline and block. This is an elementary description, but inline elements flow along with text content while block elements form an invisible paragraph box for its content. Impressive Webs has a thorough description of the many characteristics that differentiate inline and block elements.
HTML can be viewed as a series of nested elements. These nested elements form a tree-like structure. This visual representation is called the document object model, or DOM (see What is the DOM? and the image below for details):
This Added Bytes page is what Buzz is referring to below with regards to how web browsers interpret HTML:
The two key tools we learned to use in this lesson to create/review structured documents were:
CSS stands for Cascading Style Sheets. CSS controls the style of the webpage. The 'cascading' part means that CSS rules are applied not only to the elements they directly match (via classes), but also to all of those elements' child elements (i.e. inheritance). However, if a child element has multiple overlapping rules defined for it, the more specific rule takes effect.
Inheritance prevents certain properties from being declared over and over again in a style sheet. It is a fundamental building block for the abstract thinking portion of a programmer's thought process.
The name of the game is increasing productivity. Avoiding repetition by leveraging CSS is important because: