A Beginner’s Guide To Image Files

Before We Begin:

❇️ REMEDIAL: This is very basic, easy to learn information. No prior computer or technical knowledge required.

❇️ For this tutorial, we’ll assume you’re using a desktop computer or tablet & have little to no previous computer knowledge and/or experience.

❇️ Don’t worry about making mistakes; you really can’t mess up anything. You’ll get it!

Ready To Start?

Digital Images 101

The Internet is filled almost entirely of words written in text & digital images.

A digital image is a collection of many different small colored dots called pixels.

Pixels are arranged by a computer in a specific order as to represent a recognizable photographic or graphic image.

If you enlarge or magnify any digital image enough, you will see its pixels.

The resolution of a digital image is measured by its number of pixels per inch, or PPI.

Some times PPI (pixels per inch) is also referred to as DPI (dots per inch).

Every photo or image’s pixels are organized & stored in an image file.

A lower resolution digital image will contain FEWER PPI, pixels per inch.

EXAMPLE: A 800 PPI image will have less resolution than a 1000 PPI image.

A higher resolution digital image will contain MORE PPI, pixels per inch.

EXAMPLE: A 4000 PPI image will have more resolution than a 2500 PPI image.

An image file is formatted (organized) in a particular way called a FILE FORMAT.

There are many different types of FILE FORMATS available for photo & video files.

There are many digital image file formats.

Disqus accepts three image file formats.

You don’t need to bother with knowing about all the different digital image file formats; you only need to be slightly familiar with the three image format types Disqus uses: jpg, .gif & .png. Of these three .jpg (or .jpeg) is the most common, widely found image format on the Internet. Almost 95% of all still photos there are in .jpg format.

You can always find an image file’s format by looking @ the file extension on the far right:

So What In Blazes Do .jpg, .gif & .png Actually Stand For?

Ok, since you asked; however, you won’t need to remember these official names:

.jpg (or .jpeg) = Joint Photographic Experts Group

The Joint Photographic Experts Group is the name of the industry trade group of professionals who got together to create this particular image file format.

Let’s keep going; I promise this is the most technical we’ll get in this tutorial:

.gif = Graphic Interchange Format

A .gif image file can be either a single still image or a series of still images ordered in such a way as to play a small looped motion segment, usually containing no sound, over & over again, endlessly.

Understandably, such .gif files are called motion .gifs or animated .gifs. Finally,

.png = Portable Network Graphic

In general, .png image files are only used for still images & are higher quality than .jpg.

They are often used in artwork such as logos or non-photographic design elements.

You probably won’t encounter too many .png files during your daily internet adventures.

Why Do Digital Photos & Images Need Different Image File Formats?

The different image file formats are solutions to a big digital image issue: FILE SIZE.

FILE SIZE is a really big deal for computers & the Internet. Image files are usually very BIG because they contain LOTS of digital information in the form of pixels; more than simple written text words. This usually makes image files very large & more difficult to organize, store & share. Large file sizes occupy more memory & hard drive storage. They can also greatly slow down sharing & transfer. Think of an image file format being similar to a container which stores & organizes all of the photo’s pixels. The different file formats basically all differ by size; some being larger containers which hold larger amounts of digital information (pixels) while others are smaller containers which hold less.

To make it possible for photos & images to conform to a certain image file format’s container, the format compresses the photo or image to make it fit. Some image file formats compress photos more to make them fit because their containers are smaller by design.

RAW photo files are typically the largest image files because technically they are uncompressed. They also have the highest & best image resolution. The above examples are very basic & fundamental visual representations of the container & compression elements of digital image file formats & in no way represent actual scale or proportion. The greater the compression, generally the larger loss of image quality.

OK, now you know more simple, yet very important information about digital image files.

Remember to always get the most from your post!