What Cletus said. For me, shooting events, the title is mostly the event (e.g. FGCU vs Auburn Soccer 8/25/2019), the caption is something I want to say or describe about the photo. For those doing more serious sports shooting the caption would include the players names, numbers, perhaps a historical note (e.g. school prior), etc. I've seen people's captions run on for long paragraphs.
Sadly the comment from Conrad is very relevant. For example, Smugmug's new lightbox, unlike the prior, shows the title only and not the caption, which made it really pointless for my use as all the titles in a gallery were (generally) the same. Though enough people complained they are reconsidering. But if you have a use planned on specific site(s), check their display before deciding how to code.