Knowledge Base
A Brief History
Although Thomas Edison didn’t invent the very first light bulb, he created the first practical household bulb that changed how we live. A fun rumor says Edison was afraid of the dark — but thanks to his invention, the world has been shining ever since.
????️ Incandescent Lights
Incandescent bulbs use a thin filament that glows when electricity passes through. Much of the energy becomes heat rather than light, making them less efficient. Their warm, yellowish tone gives a cozy ambiance perfect for homes.
- Lifespan: 750–1,000 hours
- Color: Warm white
- Best for: Decorative or soft lighting
???? Halogen Lights
Halogen bulbs are an improved version of the incandescent type. They burn brighter, last longer, and maintain consistent light output without flicker. Filled with halogen gas, they recycle the filament and reduce blackening inside the bulb.
- Lifespan: 2,000–3,500 hours
- Color: Bright white
- Best for: Car headlights, outdoor lighting
???? Fluorescent Lights
Fluorescent lights use an inert gas and a phosphor coating to generate light. They are much more efficient than incandescent bulbs and provide a cool white or daylight tone, depending on the color temperature.
- Lifespan: 7,000–15,000 hours
- Color: Cool white to daylight
- Best for: Offices, garages, commercial areas
???? LED Lights
LED (Light Emitting Diode) bulbs are the most energy-efficient and long-lasting option today. They use semiconductors to produce light, measured in lumens rather than watts. LEDs save energy, reduce costs, and can last up to 20 years.
- Lifespan: 25,000–50,000 hours
- Color: Warm to cool white
- Best for: All-purpose home and commercial lighting
⚖️ Comparison at a Glance
| Type | Average Lifespan | Color | Efficiency | Brightness (75W Eq.) |
|---|---|---|---|---|
| Incandescent | 1,000 hrs | Warm white | ★☆☆☆☆ | ~1,180 lm |
| Halogen | 3,000 hrs | Bright white | ★★☆☆☆ | ~1,300 lm |
| Fluorescent | 10,000 hrs | Cool white | ★★★★☆ | ~1,600 lm |
| LED | 25,000+ hrs | Variable | ★★★★★ | 800–2,800 lm |
???? Energy Efficiency Example
To produce 450 lumens:
- LED bulb uses 4–5 watts
- Incandescent bulb uses 40 watts
To produce 2,800 lumens:
- LED needs 25–28 watts
- Incandescent needs 150 watts
That’s up to 80% less energy when using LEDs.
???? How to Compare LED vs. Incandescent Brightness
- Brightness is measured in lumens, not watts.
- Typical conversions:
- 40W → 450 lumens
- 60W → 800 lumens
- 75W → 1,100 lumens
- 100W → 1,600 lumens
- Check the Lighting Facts label for brightness, color temperature, and energy cost.
Tip: LEDs come in warm, neutral, and cool tones — check the Kelvin rating (2700K = warm, 6500K = daylight).
Warning: Never exceed the maximum wattage stated on your fixture.
Light Bulb Shapes & Sizes Guide
Learn how to identify different light bulb shapes and base types to find the right fit for your lamps and fixtures.
Light bulbs come in a wide range of shapes, sizes, and base types. Understanding these helps you choose the correct bulb for your lamp or fixture.
1. Light Bulb Shapes
Bulb shapes are identified by a letter (the shape) and a number (the diameter in eighths of an inch). For example, an A19 bulb is a standard household bulb measuring 2.375 inches across (19 ÷ 8).
 | A – Standard Household Bulbs Classic bulb shape used in most lamps and fixtures. Common sizes: A15, A19, A21. |
 | G – Globe Bulbs Round bulbs ideal for vanities, mirrors, and decorative lighting. Sizes: G25, G40. |
 | C – Candle Bulbs Shaped like a candle flame, perfect for chandeliers and wall sconces. Sizes: C7, C9, C11. |
 | PAR – Parabolic Reflector Bulbs Used for directional lighting like spotlights and outdoor flood lights. Sizes: PAR20, PAR30, PAR38. |
 | T – Tube Bulbs Long or short tubes used in signage, under-cabinet lighting, and decorative fixtures. |
2. Base Sizes & Types
The base connects the bulb to the socket. The letter refers to the style, and the number to the diameter in millimeters.
| Base Code | Type | Diameter (mm) | Typical Use |
|---|---|---|---|
| E12 | Candelabra | 12 mm | Chandeliers, night lights |
| E14 | Small Edison Screw (SES) | 14 mm | Decorative lamps, European fittings |
| E26 / E27 | Medium / Standard Edison Screw | 26–27 mm | Most household lamps and ceiling fittings |
| E39 / E40 | Mogul | 39–40 mm | Industrial or high-bay lighting |
| GU10 | Twist-and-Lock | 10 mm between pins | Spotlights, track lighting |
| G9 | Looped Bi-Pin | 9 mm between pins | Compact decorative fittings |
| B22 | Bayonet Cap (BC) | 22 mm | UK-standard or older fittings |
3. Reading Bulb Codes
Example: A19 E27
- A19 → “A” = standard bulb shape, “19” = 19/8 inch diameter.
- E27 → “E” = Edison screw base, “27” = 27mm diameter.
Tips for Choosing Bulbs
- Match both the shape and base type when replacing a bulb.
- European fixtures often use E14 or E27 bases, while North American ones use E12 or E26.
- LED options are available for almost all shapes and bases.