This is William “Bud” Abbott and Lou Costello doing their famous “Who’s on First” routine in 1953. Note that this routine was never done line for line exactly the same way which means some of it was improvised. Brilliant. It was done on radio, on stage, and on the newly invented television variety shows.
Abbott and Costello were an American comedy duo who were active in the 1940’s and early 1950’s.
I both heard and saw this routine numerous times growing up, it’s one of the most famous comedy sketches of all time.
I found the video embed on The Kid Should See This this morning and their post is worth reading: Who’s on First – Abbott & Costello (1953) as is the Wikipedia post linked to in my first paragraph above which gives some background on the routine.