It is a question that is asked regularly, but do we really know the difference between bitmap and vector? What are they? And why should we choose one over the other?
What are they?
Bitmap and vectors are both ways in which graphics are structured/created. Bitmaps are made up of little squares called pixels. Whereas vectors are mapped out using mathematical equations, which calculate, where the lines and points of the shapes sit in relation to one another.
How do I identify them?
Often enough the graphic type can be identified by the file extension. For example files ending in .ai or .eps are most likely vectors. Other options are .jpg, .bmp, .png, .gif or .tiff will be bitmapped graphics. Bitmap graphics can be placed and saved within .ai and .eps files but any vector graphics will be converted into pixels once they are saved as .jpg, .png, .tiff etc.
Another way to tell the difference is the quality of the graphic, as said above. Bitmap graphics will become pixelated when enlarged from their original size, whereas vector graphics will remain sharp due to the relationship between the points/nodes.
The benefits of a vector graphic are that the mathematically produced equations that created the graphic are joined via lines. This means that the graphic can be scaled and transformed without any loss of quality. It also allows the colour and shape to be altered easily.
Pantone colours can also be applied to vectors to ensure colour consistency across a variety of platforms as well as other specific colour references. A pantone colour is a standardised colour matching system. Different manufacturers in different locations can all reference a Pantone numbered colour.
Pixel graphics such as photographs can contain a huge amount of detail thanks to the small squares that are called ‘pixels’. These create the graphic. The amount of detail that can be captured in a photograph simply cannot be replicated in vector format. Bitmap formats can also be opened in standard image preview software (only certain software packages can open vector files correctly). They also cannot be edited as easily as vector graphics.
There will be times when you have to use a certain format, such as a bitmap for photographs. If the choice is allowed, and suits the aesthetic, vector formatting will allow greater flexibility in how the design can be used and will also ensure a much better quality. If the design were to be sent out as a proof or preview file – it would be a good idea to convert your graphics into a bitmap in order to protect the design from being copied.