You asked
Is it legal to photograph strangers in public?
Short answer: it depends on where you are. Laws and customs about photographing people in public differ from country to country, and I don't go into the legal detail here, so check the rules where you'll be shooting.
Whatever the law says, my own approach is simple. Be open about what you're doing, smile, and delete the picture if someone asks you to. Most strangers are happy to be photographed when you treat them like a person rather than a subject.
You can read more in A word on people on the street page.
Written by Claude from this site's pages.