identity project

I found this explanation of logo design that I think encompasses all the elements that need to be considered:

Logo design

Logo design is commonly believed to be one of the most important areas in graphic design, thus making it the most difficult to perfect. The logo, or brand, is not just an image; it is the embodiment of an organization. Because logos are meant to represent companies and foster recognition by consumers it is counterproductive to redesign logos often.

A good logo is:

• unique, and is not subject to confusion with another logo among customers
• functional and can be used in many different contexts while retaining its integrity
• presented small or large
• in full-color, but also in two colour presentation (black and white), spot colour, or halftone.
• presented on backgrounds of different colour and texture
• printed on various materials (where the shape of the product may warp the logo's shapes)
• abides by basic design principles of space, colour, form, consistency, and clarity
• represents the brand/company appropriately

Colour is important to the brand recognition, but should not be an integral component to the logo design, which would conflict with its functionality. Loud colours, like red, that are meant to attract the attention of drivers on freeways are appropriate for companies that require such attention.

For other brands, more subdued tones and lower saturation can communicate dependability, quality, relaxation, etc.

Colour is also useful for linking certain types of products with a brand. Warm colours (red, orange, yellow) are linked to hot food and thus can be seen integrated into many fast food logos. Conversely, cool colours (blue, purple) are associated with lightness and weightlessness, thus many diet products have a light blue integrated into the logo.

When designing (or commissioning) a logo, practices to encourage are

• use few colours, limit colours used to spot colours
• avoid gradients as a distinguishing feature
• produce alternatives for different contexts
• design using vector graphics, so the logo can be resized without loss of fidelity
• include guidelines on the position on the page and white space around the logo for consistent application
• do not use a specific choice of third-party font or clip-art as a distinguishing feature
• do not use the face of a (living) human being
• avoid the usage of photography or extremely complicated imagery
• avoid culturally sensitive imagery, such as religious icons or national flags, unless the brand is committed to being associated with any and all connotations such imagery may evoke.

(excerpt taken from Logo Design Article - What Is A Logo)