Web Applications for Everyone

Dr. Chuck

Request response cycles are foundation of all web applications.
This course is the most basic way to develop web applications.
End User <--> Browser (HTML, CSS, DOM, JavaScript, Jquery) <--> Web Server (Application Software e.g. php) <--> Database / Database Model <--> Database Tools (i.e. phpMyAdmin)
HTTP - Hypertext Transfer Protocol - very simple, can even be done by hand. Connect to a server, navigate to a document, send the document back. Not practical to do manually HTTP 2.0 and later. Doesn't work for all webservers.
URL Uniform Resource Locator 3 components
http:// is the protocol - how will the document be transferred
www.dr-chuck.com is the name of the webhost - where is the document located
page1.htm - which document do we send back
By default web servers communicate on port 80

<html> </html> outer tags
<head> </head> non printing info nested in html tags
title of page
links to css and javascript
<body> </body> page content, nested in html tags after head tags
index.html, index.htm, index.php, etc are usual starting web pages
use anchor tags to point between web pages <a> </a>
Absolute references <a href="http://www.dr-chuck.com/page2.htm">Second Page</a>
Relative references <a href="page1.htm">First Page</a>
white space and carriage returns usually ignored by browser (pre tag can override)
most tags have both beginning and ending tags
some like image are self closing
opening tags can have attributes <img src='somepicture.png'>
special characters for show characters used by html -
&lt - less than
&gt - greater than
&amp - ampersand
Those are main 3, but there are miscellaneous - card suits, money characters, etc.
comments: 
lists and unordered lists:
<ul><li>item 1</li><li>item2</li></ul>
<ol><li>item 1</li><li>item2</li></ol>
tables - Laid out logically - table, tr (table row), th(table header), td(table data),