I often talk about vector files, all of the logos, illustrations and infographics I design are vectors, and if I redraw a logo as a vector image I explain the reasons behind this, but here’s a little more info. Vector images are made up of points, lines and curves, rather than solid coloured square pixels. The shapes within a vector image are calculated using a mathematical equation which means the image can be scaled up without losing any quality, or pixelating/blurring, and however close you zoom in on the image, the lines will remain smooth. This applies to text as well as images, which are also converted into shapes and therefore scalable.
Your logo should be created as a vector and you can use this file on small items such as flyers, but also on large billboards. If you’re not a designer you may not be able to open these or create these files yourself (depending on the programs you have), but these are the files you need to supply to a printer, for example, to ensure high quality images for print. Vector files include eps, ai and some pdf files (as long as they haven’t been flattened). You’ll still need a jpeg or png version of your logo to be saved for you, at the dimensions needed for use on your website/social media pages or for you to use as a watermark over images etc, these are raster files so will pixellate if you enlarge them, so be sure not to!
Raster images use many coloured pixels to form a complete image, which means that when you change the size of a raster image it can become blurry. Because the number of pixels is fixed, they can’t be resized without affecting the resolution or clarity, when enlarged they become grainy or pixelated. It is important that you save raster files at exactly the dimensions you need to use them at to avoid resolution problems.
Raster files include jpegs, gifs and png files, almost all of the photos found on the internet are raster images. You can use raster files, such as jpegs when saved at 300dpi, for print, but it is important that the files are created at the actual size needed.
