Steve Jobs originally unveiled Keynote, Apple's presentation software (now costs Â£79 in the iWork bundle with its page layout program Pages and spreadsheet Numbers) back in January 2003, after beta-testing it in secret in public for a year.
Flashes (medical symptom): Flashes are visual effects where a person sees sudden flashes of light. (For flashes of warm feelings see hot flashes.) Some of the effects are like flashing lights, an arc of light, or the feeling like a light-bulb has just flashed on and off in the periphery of vision.
Or vents may pass through the roof on their own. Wherever vent pipes penetrate the roof, special flashing protects against roof leaks. (For a closer view of vent flashing, see How Roof Flashing Works.)