Caption, here, is a short description of a photograph, not a title.
Some photographers believe photographs should be able to stand alone—no text.
Some photographs, do, others, don't stand alone.
Have a look at the photograph above.
Then, place your cursor over the gray.
RMS Titanic Sailing from Queenstown for New York
Scott Jones says he was just trying calm his girlfriend down after they both had been hit by Vancouver police when the now-famous photos of them lying in the street and kissing was taken in the midst of Wednesday night's riot.
The Titanic photograph was taken by Kate Odell, and may have been purchased at auction by Stanley Lehrer.
The riot photograph was taken by Rich Lam.
Here's a funny one.

By iheartdna
This is what happens when you send your son off to your gay best friend's for a sleepover and forget to pack him a swimsuit.
Some photographs need a caption.
Captions help many photographs tell a story.
The photograph below is by Lewis Hine, who meticulously captioned his photographs:
"Carrying-in" boy in Alexandria Glass Factory, Alexandria, Va. Works on day shift one week and night shift next week. Location: Alexandria, Virginia, June 1911, Lewis Hine.
Photograph of Glass Factory Worker Rob Kidd
Joe Manning read the caption, and did some research.
I looked up Robert Kidd in the 1910 census, and there he was, in Alexandria, his father and several brothers listed as working in a glass factory.
Pretty soon, I was in contact with Amy Bertsch, at the Office of Historic Alexandria.
She was familiar with the photo, and intrigued by my call.
Within days, she had sent me a lot of birth and death records on the family.
Thanks to her, I was able to track down Robert's daughter, Catherine Dicks, who lives in Florida.
Joe Manning
Go to Robert Kidd, Page One.
Captions of family photographs, and of travel photographs, are especially important.
We forget.
But, entering the caption in a program is harder than writing on the back of a print.
1) Go to Window > Show Inspector, or press i.
2) Click the Metadata tab.
3) Select General in the menu.
4) Enter text in the Caption box.
1) Click on a thumbnail.
2) In the Information pane, double click Add a Description.
3) Enter text.
4) Click an empty area on your screen.
To add the same description to more than one photograph, do the following.
1) Select the photographs.
2) Go to Photos > Batch Change > Description.
1) Go to the Library module.
2) Click on a thumbnail.
3) Open the Metadata panel on the right side
4) Select Default in the menu.
5) Enter text in the Caption box.
1) Open the Organizer.
2) Click on a thumbnail.
3) Go to Window > Properties.
The Properties panel will open on the right side.
4) Enter text in the Caption box.
1) Click on a thumbnail.
2) Click the Add a description button.
3) Enter text.
To view a caption, go to Picture > Properties.