So, here is a glossary of lighting terms to help with your knowledge base.

• Accent Lighting

    The use of lighting to accent or highlight  objects such as artwork or plants. Also,

• Ampere or also known as Amp

  A unit expressing the rate of flow of electric current.  And,

• A-Line Lamp – like your common lamp bulb

  A type of incandescent lamp that is mostly used for indoor residential lighting needs.  Plus,

• Ambient Lighting
  

  General lighting that lights up an entire space.  Also,

• Average Rated Life
  

  An average rating, in hours, when 50% of a large group of lamps have failed.  And,

• Ballast – A device used with an electric discharge lamp
  

   Used to obtain the needed circuit conditions for starting and operating. Plus,

Ballasts have two functions:  For instance,

1) start the lamp.

2) control operation of the lamp once it has started.

• Candela or Candlepower
  

  The unit of measure indicating the luminous intensity of a light source in a specific direction. Also,

• Candlepower distribution
  

  Each lamp or lamp/luminaire has a unique set of candlepower distributions that indicate how light will be spread.  Plus,

• Color rendering index (CRI)
  

  (CRI) measures the effect a light source has on the perceived color of objects and surfaces.  Also,

• Color or Kelvin temperature 
  

  Indicates whether a lamp has a warm, mid-range or cool color appearance.  In addition,

• Compact fluorescent lamps (CFL)
  

  Lamps that employ small diameter tubes that are bent so they begin and end in a ceramic base.  Plus,

• Cool White Light

  Cool White is the least expensive and most widely used fluorescent lamp color in lighting today.   Also,

• Daylight Light

  The bluish white appearance of this lamp is similar to natural daylight toward the later afternoon.  And,

• Dimmer
  

  A device in an electrical circuit used for varying the brightness of lamps in a lighting installation. And,

• Downlight or Recessed Can
  

  A small light fixture recessed into the ceiling that concentrates the light in a downward direction.  Also,

• Economic Life

     The number of hours a group of lamps will burn before it is advised to group relamp.  Plus,

• Efficacy
  

  The rate at which a lamp is able to convert power (watts) into light (lumens), represented in lumens per watt. Also,

• Electronic ballasts
  

  The ballast starts the lamp, then limits its operating current and provides power factor correction.  In addition,

• Emergency Lighting
  

  Lighting used when the normal lighting fails.  Also,

• Energy
  

  A measure of work done by an electrical system over a given period of time, often expressed in kilowatt-hours (kWh).  And,

• Filament

  A tungsten wire positioned inside a lamp bulb to generate radiation in the visible light ranges when heated.   Also,

• Floodlight

  A lamp whose beam pattern provides a wide field of light.  And,

• Fluorescent lamp
  

  A lamp that uses an electric discharge through low-pressure mercury vapor to produce ultra-violet (UV) energy.  Also,

• Footcandle (fc)
  

  A unit of illuminance equal to 1 lumen per square foot.  Plus,

• Frost

  The glass of the lamp has a slightly opaque white appearance used to soften the light by dispersing it more evenly.  And,

• Full Spectrum

  A bulb/lamp that reproduces the full color spectrum of natural outdoor light.  Also,

• Glare

  Excessive brightness that may be caused by either direct or indirect viewing of a light source.  And,

• Grounding
  

  The grounding helps assure safety and proper lamp starting.  Also,

• Halogen lamps
  

  High pressure lamps containing halogen gases which allow the filaments to operate at higher temperatures and higher efficacies.  Also,

• High-intensity discharge (HID) lamps
  

  In HID lamps, an arc passing between two cathodes in a pressurized tube cause various metallic additives to vaporize and release large amounts of light. Also,

• Illuminance

  Light arriving at a surface, expressed in lumens per unit area; And,

• Incandescent lamps
  

  A light source that generates light utilizing a thin filament wire (usually tungsten) heated to white heat by an electric current passing through it inside a vacuum or gas-filled bulb.  Plus,

• Initial Lumens

  The measure of the amount of light a lamp produces after it has been operating 100 hours.  And,

• Instant start (IS) 
  

  Instant start  is the most energy efficient starting method for fluorescent lamp ballasting.  And,

• Lamp

  Manufactured light source; synonymous with bulb. Also,

• Lamp Disposal
  

  When disposing of spent lamps, always consult federal, state, local and/or provincial hazardous waste disposal rules and regulations to ensure proper disposal. Plus,

• Lamp Flicker
  

  Lamp flicker from magnetic ballasts can cause eye fatigue for some people.  And,

• LED

  Light Emitting Diode.  Also

• Light

  Radiant energy that is capable of producing a visual sensation.  And,

• Linear fluorescent lamps
  

  In a fluorescent lamp, an electric arc passing between cathodes in a tube excites mercury vapor and other gases and produces UV radiant energy. Also, phosphor coating on the tube then converts this energy to visible light. Plus,

• Low Pressure Sodium

  There are also HID bulbs with a sodium gas and produce a yellowish light.  And,

• Lumens-Per-Watt (LPW performance)
  

  The number of lumens produced by a light source for each watt of electrical power supplied to the light source.  And,

• Lumen Depreciation
  

  The decrease in lumen output of a light source over time.   Also,

• Lumens
  

  A unit of the overall light output such as the quantity of light expressed in lumens.  And,

• Luminaire

  A complete light fixture including lamp, reflector, ballast, socket, wiring, diffuser and housing.  In addition,

• Luminance (L)
  

  Light reflected in a particular direction.  And,

• Lux (lx)
  

  A unit of luminance equal to 1 lumen per square meter.  Plus,

• Maximum Overall Length (MOL)
  

  The total length of a lamp, from top of bulb to bottom of base, typically expressed in inches.  Also,

• Natural White

  Natural White is the closest to natural light created in the late morning to early afternoon and is the whitest of the lamp colors.  Also,

• Nominal watts
  

  Represents the energy used to produce light. Watts= Volts x Amperes.  Plus,

• Single-ended
  

  Lamps having a single lamp base or point of electrical connection.  And,

• Spotlight

  A luminaire lamp that produces a narrow beam angle designed to illuminate a specifically defined area.  In addition,

• Voltage (E)
  

  A measure of electrical potential, expressed in volts (V).  Also,

• Warm Up Time

  The amount of time from ignition of the lamp to 90% light output.  And,

• Warm White

  The color of the light from this lamp makes an area seem warmer and friendlier.   And,

• Watt

  A unit of electrical power. Lamps are rated in watts to indicate power consumption.  Finally,