1. Importance of Logo's

2. Corporate logos are intended to be the "face" of a company: They are graphical displays of a company's unique identity, and through colors and fonts and images they provide essential information about a company that allows customers to identify with the company's core brand

3. purpose
Logos should be unique and comprehensible to potential customers
A logo should help convey some information about the company, or be designed in a way that gives some sense of meaning about the company or its industry
For example, cutting-edge firms and tech companies tend to have angular logos to convey speed, while service-oriented firms have rounded logos to provide a sense of service and trust.

4. Brand identity
Logos are the visual component of a company's overall brand identity – how that business wants to be perceived by consumers
A well-designed logo can contribute to business success, while a substandard logo can imply amateurishness and turn off potential customers
A well-designed logo implies a degree of professionalism and competence that could help steer potential new clients toward selecting the business 
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5. Common mistakes
Small businesses often play it fast-and-loose with logos - paying insufficient attention to their proper size and positioning and surrounding them with materials--including clipart--that compete with them visually
Designing Your Logo