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.
Screw-in types can be used in place of incandescents in standard lamp sockets. Available in a wide spectrum of colors. Warm white tones best duplicate the color of incandescents. Today's fluorescent bulbs come in a wide selection of sizes and can produce warm tones of light similar to those of incandescents.
Light Bulb Types. LED light bulbs or lamps utilize light-emitting diodes in order to produce light. LED is a âsolid-stateâ technology, which means that the materials used to generate the light are encased within a solid material. Practically, this translates into a lamp with a rated life much longer than those using non-solid-state technology (such as incandescent, halogen, and fluorescent).