Bacon was smoked and salted meat, known as pork, from the back and hindquarters of an Earth pig, often eaten as part of breakfast as a side with eggs.
In 2004, the Fiesta Salad at the fast food restaurant Burgerland in Detroit, Michigan could have bacon added to it for only seventy-five cents. (ENT: "Carpenter Street")
In 2151, Doctor Phlox listed bacon as one of Malcolm Reed's favorite foods alongside sausage, eggs, and pancakes. (ENT: "Silent Enemy")
Miles O'Brien often enjoyed bacon and eggs for his breakfast. (TNG: "The Wounded")
Rom ordered bacon and eggs with a side of corned beef hash at Quark's before reporting for his duty shift in 2373. He later found out it didn't agree with his stomach, though. (DS9: "The Assignment")