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File Types and Organization

Every file has what is called a "type" or "extension" that determines what program will open it and how it behaves. By default, modern operating systems often hide the file extension, but you can show them by following these steps. As you progress through this class, you will probably encounter a few types of files you may not be familiar with. Here is a quick introduction to the different files you will come across and what they are used for:

  1. Drives
  2. Folders
  3. HTML files (.html)
  4. Stylesheets (.css)
  5. Images (.png, .gif, .jpeg, and more)
  6. Spreadsheets (.xlsx, .xls)

Video Summary

Folders

Folders, also known as directories, are containers that hold other files. They are very helpful for organizing your work, and the very first thing you should do for this class is create a CS100 folder. If you are in the lab, it should be in your Network I:: drive, but if you are using your own computer you can place it wherever you will find it easily.

While folders are usually great, they can also cause problems in this class. When you are building websites, the files have to have access to each other for links and images to work properly. Until you are more experienced with websites, we would STRONGLY RECOMMEND YOU DO NOT USE EXTRA FOLDERS FOR THIS CLASS. Using folders on Hyperion often causes the marker to be unable to find a student's assignment, and can result in the student receiving a 0 despite doing the work. For now, just keep all of your files in one CS100 folder.

Zipped folders (.zip)

Zipped folders are used to compress the files within it to a smaller size, allowing them to be more easily transferred and shared, such as through email. To zip a folder, simply right click on it, select "send to", and then zip. In order to access the files again, you would need to unzip the folder on the destination device.

HTML Files (.html)

HTML files are basic webpage files. When you open an HTML file, a web browser will launch and determine the appearance of the webpage through the use of HTML tags, which you will learn about later.

In order for the file to actually behave like a webpage, it MUST have the .html extension: If you are trying to check a page and it is opening as a text document (.txt), open that file in your text editor and resave it with the .html extension.

Cascading Stylesheets (.css)

Cascading Stylesheets are files that contain all of the instructions on how to format, or present, a webpage. These files are not webpages and should never contain HTML code - rather, they have their own set of rules that will affect any page you link, or "attach", them to.

Images (.png, .gif, .jpeg, and more)

There are many different types of images. The different extensions determine how the image is "encoded", or saved, onto the computer: different encoding methods have different quality and take up different amounts of memory. When you are building a website, it doesn't necessarily matter what the file extension of the picture is, as they will all work. What matters is that you know what that file extension is, as you will need it when you are trying to add it to a page.

Spreadsheets (.xlsx, .xls, .csv)

Spreadsheets generally have an icon for the program that they open with, such as an E for Excel. .xlsx is the newest version of Excel workbooks, and while very old computers sometimes can't open them, that shouldn't be a problem in this class.