We are lucky to live in a time period in which we have movies available to us, thanks to On-Demand, Netflix, and cable.

In the 20th century, there were barely any options to watch movies. You could go to the movies or wait for it to come on T.V.

According to studies, most millennials do not care for older movies. Some believe that black and white movies are boring. As an old soul, I contend that old movies are fascinating. They give us a sense of history, perspective, and allow us to relate to our grandparents.

While there are many definitions of classic movies, I am talking about classic during my grandparents' era from 1939 to 1973. Grandparents are here to tell us about the movies that were famous and in theaters back then.

Classic movies have made strong impacts on the audience and still do today. Here are 23 movies you must see, which are filmed from 1939 to 1973:

1. The Wizard of Oz (1939)

"Toto, I have a feeling we're not in Kansas anymore."

2. Gone With the Wind (1939)

"Frankly, my dear, I don't give a damn."

3. Casablanca (1942)

"Here's looking at you, kid."

4. It's a Wonderful Life (1946)

"Teacher says, every time a bell rings an angel gets his wings."

5. Miracle on 34th Street (1947)

"Christmas isn't just a day, it's a frame of mind."

6. All About Eve (1950)

"Fasten your seatbelts, it's going to be a bumpy night."

7. A Streetcar Named Desire (1951)

"Stella! Hey, Stella!"

8. The Quiet Man (1952)

"When I drink whiskey, I drink whiskey. When I drink water, I drink water."

9. Singing in the Rain (1952)

"I'm singing in the rain, just singin' in the rain, what a glorious feeling, I'm happy again, laughing at the clouds."

10. Roman Holiday (1953)

"I'd like to do just whatever I like the whole day long."

11. Rear Window (1954)

"A murderer would never parade his crime in front of an open window."

12. Sabrina (1954)

"You are unhappily in love. A woman happily in love, she burns the souffle. A woman unhappily in love, she forgets to turn on the oven."

13. Rebel Without a Cause (1955)

"Boy, this is gonna be one terrific day, so you better live it up."

14. An Affair to Remember (1957)

"Winter must be cold for those with no warm memories."

15. South Pacific (1958)

"I'm going to wash that man right out of my hair."

16. Some Like It Hot (1959)

"I don't want you to think I'm a drinker. I can stop anytime I want to, only I don't want to."

17. Breakfast at Tiffanys (1961)

"We belong to nobody and nobody belongs to us. We don't even belong to each other."

18. West Side Story (1961)

"People aren't killed by bullets and guns; people are killed by hate."

19. Mary Poppins (1964)

"Supercalifragilisticexpialidocious!"

20. The Sound of Music (1965)

"The hills are alive with the sound of music with songs they have sung for a thousand years."

21. Willy Wonky and the Choclate Factory (1971)

"Come with me, and you'll be in a world of pure imagination."

22. The Godfather (1972)

"I'm going to make an offer he can't refuse."

23. The Way We Were (1973)

"Your girl is lovely Hubbell.