firework wiki:
assified as low explosive pyrotechnic device used primarily for aesthetic and entertainment purposes. The most common use of a firework is as part of a fireworks display.Fireworks (devices) take many forms to produce the four primary effects: noise, light, smoke, and floating materials (confetti for example). They may be designed to burn with colored flames and sparks. Displays are common throughout the world and are the focal point of many different cultural and religious celebrations.
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Halftone wiki:
ftoning is a method of printing shades using a single color ink. By varying the size or density of dots, the eye can see a shade somewhere between the solid colour and the colour of the background paper. The effect has its limits, and when the dots get too small or spaced too far apart, the eye can start seeing individual dots again.
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