Aunt: I guess you’re too young to know the Beatles.
Niece: Actually, I love the Beatles!

“Actually” has a similar meaning to “really” or “in truth”. We often use it to introduce an unexpected fact. It can help correct a wrong assumption. “I don’t suppose you know this cartoon.” “Actually, I watch it with my daughter all the time.” It can also emphasize that something really happened. “He actually touched the spider with his hand.”