Several blog posts have covered the many file extensions that are out there for graphic files, along with their uses. Rather than create another, I thought I might take a moment to direct you to some of the posts I have found most helpful and that I reference to my clients.
What I would add to these articles is that most of them are talking about ideal situations. If you are working with a trained industry professional, a designer should have provided you several file types for the different types of use. What I run into working with small to medium sized businesses does not always fit what is standard. The typical situation I run into is a business owner's friend's daughter likes to draw, so she created a logo or graphic using templated software on a non-designer friendly program. The result is something that falls in one or more of the following categories:
1. The graphic is either good to be printed or to be used digitally, but not both.
2. The colors of the graphic seem to be slightly different from when they are viewed on a screen and when it is printed.
3. The graphic takes way too long to upload when someone visits their site.
4. The business owner was only given one or two file types.
5. The only versions of the logo provided have a white or black box around them.
6. Vendors and printers keep asking for a vector file when all they have is a .jpg.
7. Vendors and printers are saying the .pdf file provided is not a vector file because it has a .jpg in it.
8. The graphic looks great, but does not look good when put on the side of a van or shrunk down to be put on a pen.
If you find yourself experiencing one of the above situations, don't fear. As a graphic designer I spend a fair amount of time recreating logos so that business owners can have the file types needed to make their business look clean and professional. It is important to use the right files at the right times. So, enjoy these great articles by some industry professionals.