Well, it was the first underwater photograph of a person, or one where it's possible to really see anything.

The very first was taken in 1856 by William Thompson:

Which came just thirty years after the first photographic image of any sort was captured in 1826 by Joseph Nicéphor; you can just about make out the buildings here.

Then came Louis Daguerre, who had worked with Joseph Nicéphor, and in the 1830s created his own photographic method: the daguerreotype.

This photograph of the Boulevard du Temple in Paris, from 1838, is the oldest to feature humans - you can see them in the lower left.

The first self-portrait (or selfie, perhaps...) seems to have been taken in 1839 by Robert Cornelius.

And in 1840 John William Draper took the first - or, at least, oldest surviving - photograph of the moon.

Five years later, in 1845, Louis Fizeau and Leon Foucault managed to photograph the sun.

But photography wasn't only changing science.

An engraving was made of this photo, taken during the 1848 French Revolution, and printed in a Parisian newspaper called L’Illustration.

The first time photography had been used in news media.

The oldest surviving aerial photograph, it seems, was taken by James Wallace Black in 1860. He called it "Boston, as the Eagle and the Wild Goose See It."

A French photographer called Nadar had already made aerial photos two years prior, but these have not survived.

In 1861 came the first ever colour photograph. It was taken by James Sutton and based on the work of Thomas Clerk Maxwell. What we're looking at here is a small tartan ribbon:

In 1847 Thomas Martin Easterly made a daguerreotype of lightning, but that original has been lost and only survives as a copy (left).

And so William Jennings' photo (right) taken on 2nd September 1882, is the oldest known photo of lightning.

The first X-ray was taken in 1895 by Wilhelm Conrad Röntgen, just a few weeks after he had discovered this new form of radiation; it was of his wife's hand.

The first photo of the Earth from outer space was taken in 1946 by the V-2 No. 13 Rocket. Other, more famous photos of the Earth would come, but this is where it began.

And the first ever digital image was created in 1957 by Russell Kirch. He led the development of a digital scanner and this, a photograph of his son, was the first one they scanned.