What is 'dpi'?

In printing terms, 'dpi' stands for 'dots per inch'. The more dots in an inch, the sharper an image will be.
Computer monitors are around 72-96dpi, newspapers are around 160-200 dpi and most other printed products are 300 dpi.

If you use a magnifying glass to look at a newspaper you can see the dots quite clearly, and with a good quality magazine you can see the dots still but there are more of them. This is why an image in a magazine can look sharper than in a newspaper.

If you take a photo with a digital camera, the image can have a range of dpi's. The higher the resolution of the image, the higher the 'dpi' is. When submitting content to a design studio if you're not sure about the 'dpi', it is generally best to submit images in the highest quality (usually the largest size).