Where does this come from, and can I check it?

Century-old Edison screw specifications remain global electrical fitting standards. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a everyday life fact?

Yes. It sits on the Everyday Life shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Standard light bulb bases use Thomas Edison's 1909 screw thread

Century-old Edison screw specifications remain global electrical fitting standards

Thomas Edison designed the classic screw thread base for electric incandescent light bulbs in 1909, modelled after kerosene lamp metal caps. Designated by letter E, standardised bases like E27 remain global electrical fittings across residential homes over a century later.

Light bulb socket E26 three way — Hustvedt · CC BY-SA 3.0 · licence · source

Where this comes from

NIST

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

Go further

History trivia Electricity Cost Calculator

More facts like this

Incandescent lightbulbs emit mostly heat rather than visible lightOver ninety per cent of electricity consumed by glowing tungsten filaments becomes heat National power grids synchronize electrical generator frequency across countriesNorth America operates at sixty hertz while Europe and Asia use fifty hertz AC frequency Standard C4 envelopes are sized to fit flat A4 paper sheetsISO envelope series measurements allow flat A4 documents to slide in smoothly Standard A4 paper uses a unique mathematical aspect ratioThe side ratio of one to the square root of two preserves proportions when folded Standard railway tracks measure four feet eight and a half inches wideTraditional wagon wheel spacing established global railway track gauge dimensions Pen caps contain ventilation holes to lower suffocation risksInternational safety standards mandate airflow channels inside swallowed pen caps

Tags: lighting, electricity, standards

Standard light bulb bases use Thomas Edison's 1909 screw thread: the short answers

Where does this come from, and can I check it?: Century-old Edison screw specifications remain global electrical fitting standards. The figure is taken from NIST, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.