Vector VS Raster

Often when dealing with designers or programmers you will run into two terms; Vector and Raster. Each is suited for specific purposes and it is highly important for you as a consumer to understand the differences between the two. If you don't, you can run into problems with your projects, and it can cost you more money to get what you wanted in the first place.

WIKIPEDIA explains Vector Graphics

Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical equations, to represent images in computer graphics.

Vector graphics formats are complementary to raster graphics, which is the representation of images as an array of pixels, as is typically used for the representation of photographic images.[1] There are instances when working with vector tools and formats is the best practice, and instances when working with raster tools and formats is the best practice. There are times when both formats come together. An understanding of the advantages and limitations of each technology and the relationship between them is most likely to result in efficient and effective use of tools.

And

WIKIPEDIA explains Raster Graphics

In computer graphics, a raster graphics image or bitmap is a data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium. Raster images are stored in image files with varying formats (see Comparison of graphics file formats).

A bitmap corresponds bit-for-bit with an image displayed on a screen, generally in the same format used for storage in the display's video memory, or maybe as a device-independent bitmap. A bitmap is technically characterized by the width and height of the image in pixels and by the number of bits per pixel (a color depth, which determines the number of colors it can represent).

The printing and prepress industries know raster graphics as contones (from "continuous tones") and refer to vector graphics as "line work".

SO - what does THAT mean?

Ideally, when you contract design work, you should specify that you want the working files as part of the package. FPS always gives you the working files if you request them. This gives you total control to take the design to another vendor, to edit things yourself, or to just have a backup of the file. Be cautious when hiring a designer as many will not give you these files - as they are afraid of loosing your future business when you need edits. These files are often "held for ransom" and can cost you a lot of aggravation and a lot of extra money.

Beyond the actual working files, the real concept to remember is that as a client, you want a VECTOR graphic for any type of logo, icon, or line based illustration. This ensures that you can scale the image without loss of quality. It also ensures that the image is not connected to a background color - so you can place it on top of watever you like.

You want a RASTER graphic for all photographs and illustrations that are more painterly or heavily gradieated than is capable of a VECTOR graphic.

OK - so how do I know the difference?

WIKIPEDIA States it Best

BUT, here is a general guide:

.gif = Vector, but may not be scaleable.

.jpg = Raster

.eps = Vector, the best solution for logos, icons, illustrations.

.tif = Raster

.png = Succesor to .gif - a sort of Hybrid.