A preamble is usually used for formal documents; you wouldn't include one in a text to your best friend. noun-A preliminary statement, especially the introduction to a formal document that serves to explain its purpose. noun-An introductory occurrence or fact; a preliminary.
Halogen bulbs produce a bright white light. They become much, much hotter than other types of bulbs and should not be used near combustible materials or touched during or shortly after use. Fluorescent: These tube-shaped lights are often used as overhead lighting for large areas such as retail stores or home basements.
Current labeling already helps make the switch from thinking in watts to thinking in lumens. The next three slides show three packages for three different types of A19-shaped light bulbs â incandescent, LED and CFL â that all produce approximately the same lumens. This 40-watt incandescent bulb equals 500 lumens. Photo: Inset from Philips light bulb package.