A logo is a flag. A shield. Your family crest. A chevron you hoist up and point out into the world to rally the like minded, to convert the new faithful, and to inspire those already on board. Your calling card explaining who you are now, and if you build it right, starts the conversation about who you're going to be, often without you needing to be there. 

That may sound a bit rhapsodic, but your mark, however small and conversational or bold and razor-edged, still carries the DNA of a million powerful symbols with it. Perhaps that's why nailing down a perfect logo can be such a tricky bit of witchcraft. What you are essentially doing is asking a piece of color, shape and symbology to carry the heavy load of ambassadorship out into the world for you. 

It can be easy, too easy, to fall into the trap of trend and personal preference when creating or deciding on your mark. Something that seems to dash along perfectly on all your materials now could disappear in sea of similar logos if too trendy, or oblique and nearly inscrutible if too personal and quirky.

I've put together this chart to navigate these sometimes murky waters.  It is not meant to act as the be-all and end-all encyclopedia of logotype, but to give you a basic map to the various "ways in" to deciding what your clever little ambassador should look like. I've chosen several famous marks and noted them according to their significant attributes, their core strengths and tones. When reviewing these logos, note what attributes speak to you most, and use that list to guide you when designing your logo.

In time I'll certainly find myself adding to this list, but for now here are a baker's dozen of some of recent-history's best logos to help you understand the how and the why of making your flag.