Types of graphics: raster vs vector

Raster

An image made of lots (hundreds, thousands or millions) of tiny pieces of colour information. The pieces may be either pixels (colour blocks on an electronic screen) or dots ("blobs" of ink on a printed item).

Some raster file types:

• jpg (jpeg)
• psd - Photoshop File
• png
• tiff (tagged image file format)
• bmp
• gif

Also - TO BE CONFIRMED

• PSP – Paint Shop Pro File
• XCF – Gimp File
• CPT – Corel Photo Paint

Vector

An image drawn using points, lines and mathematical curves.

• A 1” x 1” square raster image a at 300 dpi has 300 individuals pieces of information
• A similar vector image only has four points (one for each corner) and the instruction that they form a square; software that processes vector images uses maths to connect the dots correctly.

Usually used in logos (which may need to be printed in very different sizes) and where a sharper finish is required.

Some vector file types:

• AI – Adobe Illustrator File
• EPS – Encapsulated Post Script
• PDF – Portable Document Format
• PSD – Photoshop File   (yes, Photoshop can work with both raster and vector formats)
• SVG – Scalable Vector Graphic
• CDR – Corel Draw File
• PLT – Plot File