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.
Compact fluorescent bulbs, also known as CFLs, contain a fluorescent tube and ballast in a single unit, and are designed to replace incandescent bulbs. A 23- to 27-watt CFL provides the same amount of light as a traditional 100-watt incandescent bulb while consuming about 75 percent less energy.