What is the plot of Jojo's Bizarre Adventures?

JoJo's Bizarre Adventure is a manga and anime about a family called the Joestars with a name that can usually be abbreviated to Jojo. The story takes place in a world similar to the real world but with added supernatural forces such as inner energy personifying into reality called Hamon. In the later parts, a new force emerges called Stands that give each user an additional power. The story is split into parts following a descendant of the Joestar family and the antagonist is usually Dio Brando or an associate.