Vector vs Raster files - what's the difference?
When generating artwork you have two formats in which you could work, depending on the software you’re working in: vector and raster. But what does that mean?
Well, it’s just a way of grouping how information is displayed on a screen. Raster images are essentially just a collection of dots (pixels) that are arranged on the screen to display a particular image. Vector graphics, on the other hand, are created from paths derived from a mathematical formula that can be manipulated – lines, basically. For simplicity’s sake, raster is made of dots and vector is made of lines.
The difference between them is really just a question of quality and flexibility in regards to future use. Raster graphics, made up of all their dots, often suffer from pixelation. This is because when you enlarge a collection of tightly-packed dots, the dots themselves don’t get bigger. Instead, they move further from each other to fill up the new space in equal proportions, leaving a lot of white space between each of the original pixels. The program you’re using (Photoshop, for example) is clever enough to guess what colours to fill these empty pixels with, based on the surrounding colours, but the more you demand of it, the less accurate it can be. This is why you can enlarge a raster graphic a little without too much compromise, but the further you push it, the fuzzier it becomes.
Vector graphics, however, are far more capable of this. Because their lines are backed up by that mathematical formula, they enlarge proportionally in every direction, just as you’d expect them to. This means that the computer never has to fill in empty space with guesswork and the image quality retains its integrity no matter what you do to it.
For these reasons, vector artwork is, generally speaking, superior - particularly for items such as logos, patterns, wall-art, etc, that could potentially be used at a substantial scale (think billboards, for example). However sometimes the programs you're using dictates which you'll be working in. For example, here's a brief list of common design software (both professional and hobbyist) and whether they produce (primarily) vector or raster designs:
Adobe Illustrator: Vector
Adobe Photoshop: Raster
Affinity Designer: Vector
Coral Painter: Raster