What type of products or services your company supplies… etc.
A symbol is an abstract illustration with your company name typeset alongside.[example: the Nike Swoosh, McDonald’s Arches, Wachovia logo]. A logotype incorporates your company name into the logo itself.[example: IBM, Microsoft, Coca Cola].
For example: Some Real Estate firms want Roof, House, Key, Door, Initials, Pyramid, Pillar etc.
Some Christian Churches want to avoid the Cross, Real Estate firms want to avoid using the roof as a symbol in their logo.
This would help the designer avoid the style/image that may annoy you