You're listening to 20,000 Hertz.

Nothing says Summer quite like the crack of a baseball bat.

Like most major sports, baseball is full of iconic sounds.

They're the calls of the umpire. The vendors selling

popcorn and hot dogs. Not a ball game without a hot dog. Who wins a hot dog? The commentary from the

announcers. It's at hard to right field. This ball is back and it is gone.

But there's one sound that's completely unique to baseball.

Or should I say, one song.

This song is so well known that virtually every American can sing it,

whether we like baseball or not.

At least, we can sing the chorus.

The verses, well, that's another story.

Here's Lizzie Peabody, host of the Smithsonian Side Door podcast.

On July 16, 2008, Dan Piazza got up from his desk at the Smithsonian's National Postal Museum and left work early.

He hopped on the metro and set off across town, tucked in his bag, a personal invitation to an

event at the White House.

Well, you had to be on a list and have an invitation.

Anyone who had an invitation had to submit their Social Security number in advance before coming on to the South Lawn of the White House.

There on the lawn, he joined the gathering crowd and took a seat under the glaring summer sun.

It was hot. It was very hot. They gave out little fans because it was so hot.

And how many people, about how many people were there, do you think?

I'm certain there were hundreds. There might have been thousands of people on the South Lawn of the White House watching this, this T-ball tournament.

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