[6] Much of Hero's original writings and designs have been lost, but some of his works were preserved in manuscripts from the Byzantine Empire and, to a lesser extent, in Latin or Arabic translations.

[8] However, Hero does not explicitly say this, his brief mention of the eclipse is vague, and he might instead have used some earlier observer's data or even made up the example.

[9] Alexandria was founded by Alexander the Great in the 4th century BC, and by Hero's time was a cosmopolitan city, part of the Roman Empire.

[10] It has been inferred that Hero taught at the Mouseion because some of his writings appear to be lecture notes or textbooks in mathematics, mechanics, physics and pneumatics.

[21] Today, however, his name is most closely associated with Heron's formula for the area of a triangle in terms of its side lengths.