A Complete Guide to Digital Files and Their Purposes
If you are just starting out on your graphic design career, you might still not know all the different types of digital file formats we use on a regular basis. We’ve put together a full collection of all the important types, most of them you might already recognize. Along with those we’ve also included some less known types.
We have separated this list into three main groups: Raster, Vector, and Video
Digital image file formats
The following file formats are the ones that define digital images, both graphic design visuals, and photography. All digital image file formats can be separated in two important groups; raster or vector.
Raster File Formats
Raster files are essentially made of pixels. Raster files can be in high resolution and low resolution. It’s easy to go from high quality to low quality but once a file is low-quality it cannot be made high quality again. It’s all about the number of pixels in the space. A low-quality raster image looks blurry and pixelated for this reason. The biggest difference you need to know about lo and high-quality raster is the Dots per Inch measurement (DPI). Images online are ok at 72 dpi but for an image to look good on print, it needs to be 300 dpi.
Jpeg is the most common image file format, most images on the internet will be jpeg. Images in this format are compressed and need to be the exact size needed, especially when printing. Once compressed, it loses quality and will keep losing it as it keeps getting compressed.
This is the second most common image file format, the biggest difference with Jpeg is that Png images can have transparent backgrounds. This is the best type of file for any cut-out shape that can be placed on another image or background. Png is not suitable for print.
A gif file is most commonly known as those animated images we see all over the internet. They are very low quality and can only reproduce 256 colours. That’s why when you try and make a gif from a collection of high-quality photos, it doesn’t look so great.
Raw is a file format that applies to photography directly. When you take a photo with your DSLR camera (and some phones), you get two files; one jpeg and one raw. The raw file is like a digital negative, which is what photographers use to edit on programs like Lightroom. Editing a photo while it’s on Raw maintains the quality of the image and has better colour composition.
The tiff file format is a common file format for high-quality images. Printers sometimes prefer this file format for printing large scale photography and design. It’s the most versatile of large files, as most programs can open it.
Photoshop files are raster because Photoshop is a raster file editor. In-process files are saved in PSD format and can only be opened with Photoshop or at the most Pixelmator. This type of file has layers and smart objects and can be used for mockups of any type.
Vector File Formats
A vector file is one that is infinitely scalable. One same file can be used for stickers and for billboards. If you look at a raster file next to a vector file you can tell that the edges of the colours are completely different. When you zoom in, vector files have curved or perfectly straight lines.
This file format is a common one used by designers for design projects. Its used to transfer images from one program to another and can be opened on Adobe Illustrator, Photoshop, Corel Draw, and Quark. Inkscape won’t open Eps files. Printers prefer this file format for silkscreening and marketing materials, like printing on plastic.
An SVG file is good for the web because it maintains its high quality when a website is seen on a desktop and on mobile. Svg files can be images or text. It can also a be cut-out image with a transparent background. In-process files created with Inkscape are saved as Svg.
Files created with Adobe Illustrator are save in Ai format. Files in this format can be transferred seamlessly from any computer to another as long as it’s on Adobe Illustrator. Vector files downloaded from Freepik are usually in Ai format, ready to be edited seamlessly.
Can be both
The thing about Pdf files is that they can hold both file formats inside it. The complete document is compressed and very practical but if an image started as raster it will save as raster. The same goes for a vector file. Pdf is a good format for long documents with images like e-books. Printers also prefer Pdf for things to be printed with lots of text that needs to maintain its high quality.
Over to you
Knowing all these types of file formats is an essential part of working as a graphic designer. We work with photography, graphics, and text and knowing how to handle the files is really important.