Heliograph is a word derived from helios (Greek Ἥλιος / ἥλιος "sun") and graphein (γραφειν "to write"). It has several uses:
- the heliograph, a device used for optical signalling
 - a type of sunshine recorder
 - a solar telescope, a telescope especially adapted for viewing the surface of the Sun
 - heliography, the photographic process used to make the earliest known permanent photograph from nature
 
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