After years of working with countless designers (and admitting to a few design quirks of my own), here are some additional items to add to the list.
You Know You’re A Graphic Designer When You …
Think Helvetica is beautifully elegant and Arial is functional but clunky.
Talk openly and frequently about PMS (Pantone Matching System) but don’t understand why everyone keeps giving you funny looks.
Choose/use fonts to “match the personality” of the targeted reader.
Hate Times New Roman with unwavering intensity.
Spend hours and/or days of unbillable time searching for THE PERFECT FONT for a specific project.
Reject 95% of fonts for perfectly sound reasons (the dot over the lower case “i” is too frivolous or the capital “T” is ugly).
Obsess about leading and spend more unbillable hours tweaking it.
Prefer caffeine through an IV drip.
See a significant difference between copy set at 10 v. 9.5 pts. (Whew. That’s MUCH better!)
Know Rubine Red is actually pink.
Have intense, heated discussions about the merits of Serif v. Sans Serif. Sometimes, these “discussions” are with yourself …
Have passionate opinions about red, blue-red, chinese red, tomato red, barn red …
Believe Small Caps are much more visually pleasing than All Caps.
Notice that a Sans Serif font has a rounded, square or angled end, and these subtle differences are significant (to you).
Know that “coated” and “uncoated” have nothing to do with fashion, attire or weather.
Have distinct and explicit x-height preferences.
Realize when a client tells you he loves the copy typeface and finds it quite readable that sometimes font choice really does matter (Bookman Light ITC).
Can spot a 1/64" problem with alignment from across the room.
You Know You’re a Graphic Designer When …
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Original list: http://nheerdesign.wordpress.com/2007/05/31/you-know-youre-a-graphic-designer-when/