By working in the field of digital design, I am faced with a wide range of file formats every single day. Although distinguishing the difference between digital files has become second nature to me, I often forget that this is not common knowledge to everyone in the workplace. Especially when dealing with logo design and print projects, I find that clients and other non-designers often do not fully understand the difference between file extensions.
To bridge the gap, I’ve put together a quick overview of a few of the most common file types, the differences, and when you should use them.
File Formats 101
The main difference between raster and vector image files comes down to the way in which they are made. Raster image files are composed of pixels, and vector graphics are made out of paths. Here’s what you should know about the two:
Vector
- Created using specialized vector software (ex. Adobe Illustrator)
- Made out points and curved paths using the Bezier system
- Infinitely scalable and never loses sharp resolution
- Great for printing everything from small business cards to large billboards
- Smaller file size than raster images
- Source files used to send to printer
Raster
- Created from pixels
- NOT infinitely scalable
- Photos taken with digital cameras
- Will appear blurry if you increase its size too much
- For print quality, aim for a resolution of 300 dpi (dots per inch)
- Larger file size when increased in size and resolution
Common Vector File Formats
.EPS – Encapsulated PostScript File
- Most common vector format
- Compatible with all operating systems
- Widely used in the print industry
.AI – Adobe Illustrator File
- Adobe Illustrator’s native file format
- Source files for creating logos and other vector images
.SVG – Scalable Vector Graphics File
- Used for 2-dimensional graphics
- Ideal for logos and icons on websites
- Supported by all modern browsers
Common Raster File Formats
JPG/JPEG – Joint Photographic Experts Group
- Most common file format for images
- Uses a lossy compression
*Note: Lossy compression – irreversible compression of an image
to reduce file size, but in turn reduces the quality.
PNG – Portable Networks Graphics
- Another common file format for images
- Lossless compression
*Note: Lossless compression – compression of an image
to reduce file size without reducing the quality
GIF – Graphic Interchange Format
- Ability to create short, animated images
- Use raster images and a limited number of colors (256 colors)
TIFF – Tagged Image File Format
- Lossless raster image that allows users to save an image with compression as an option
- Larger file sizes than a normal JPG
PSD – Photoshop Document
- Image created from and compatible with Adobe Photoshop
- Source file used to edit images using layers
- Used to flatten layered files into other file formats
(.JPG, .PNG, .GIF, etc.)
Although this list covers a handful of file types, keep in mind that there are many more out there – this is simply an overview of those that are most commonly used. So, the next time you are speaking with a designer, print-shop, or are simply guessing which file type you should be using for a specific project, feel free to bookmark this blog to make sure you are using the right one.
