For a small business owner that has to deal with graphic design, knowing what raster and vector mean is critical.

Sure it's an "industry" term, but to know how to fully utilize your brand's design elements, it's worth a short vocabulary lesson.

Raster

Raster images are what you normally think of as digital photos (.jpg, .png). They are made up of thousands of little squares, each a different color. Basically, they're complex, but when you zoom in, or stretch it too large, it looks blurry (you see the "pixels" or squares). This is the type of file that works great for photos, because they show great detail and shading. They are optimized for one resolution, and the files are usually pretty dang big.

Vector

Vectors are essentially files that contain math. It's kinda like magic. The computer saves points on a path, and generates the lines and design based on where you place it. Basically, it can be stretched to the size of a billboard or squeezed into a half inch box, and it will look the same. Smooth lines and angles, no little squares. There are limited color effects, and the file size is much smaller. Vectors are great for logos, infographics, and simple artwork that will need to be scaled to a variety of sizes. Common file types are .ai, .pdf, .svg and .eps.

Why should I care?

You need to know this to know how to use your design files, and what files you should have in the first place!

A professional graphic designer will provide you with the vector version of your logo, which is what you'll need to use for larger projects moving forward. That's the file you send to your web designer, the person who prints your merch, big poster/billboard ads, etc. The raster files are your photos and designs that have been made for specific sizes like stationery, email signatures, social media graphics, etc.