English Tea (or English Breakfast Tea as it tends to be called on the continent) is generally a little stronger to taste and is more commonly served with a bit of milk to make it creamier. Continental tea tends to be a less stronger blend and is often just drank sans milk and sans sweeteners.
Though the reality is there's very little difference between them, just that most people on the continent will think you're weird for putting milk in tea.
(By "continent" I'm mostly referring to main-land Europe)