Have you ever met an astro twin? If you want to get technical, astro twins are two people born on the same day, month, year, time, and place (making their birth charts completely identical). Though meeting such a person is extremely rare, we do often encounter "date twins:" those that are born on the same day, month, and year, but at a different time or place (or both a different time and place). Alternatively, Llewellyn's New A to Z Horoscope Maker and Interpreter gives the following definition: Astro twins are "[t]wo people with the same Sun sign, Moon sign, and Ascendant."
Since astro twins (and, to a lesser extent, date twins) share the same natal chart, they should be alike in every