How many TV shows have changed the world?

The list is short. Indeed, you could probably count it on your two hands (and, okay, maybe a couple of toes). But somewhere on that list, you essentially have to have Sesame Street, the educational stalwart that turns 45 this month.

The show began on National Educational Television, then transitioned seamlessly when NET became the still existent PBS. And its artistic importance to children's television cannot be overstated. It codified and created many of the ideas about how TV could be used to teach kids that we still use today. But its influence went well beyond that. By becoming such a bedrock of educational television, Sesame Street changed the country — and eventually the world.

Don't believe me? Here are five good reasons.

1) Sesame Street invented children's programming as we understand it — and changed adult programming too

It's not as though the show invented children's educational programming out of whole cloth. There were a handful of pioneers in the field that preceded it onto the airwaves. But for the most part, pre-Sesame Street children's programming was a collection of junkily animated programs that appealed to the lowest-common denominator. People figured kids would watch pretty much anything (because they will).

The late '60s were by and large the worst period for American television

Sesame Street changed that. Even if you strip out the educational aspects of the program, it was filled with beautifully realized, well-developed characters who could speak to kids at their level. It was filled with weird humor and great songs. And it was filled with an endless sense of possibility, with the idea that just about anybody — from a giant talking bird to the first lady — could come around the corner and feel at home within its environment.

The television world of 1969 wasn't great. The late ‘60s were by and large the worst period for American television, filled with programs that essentially didn't care if they shoveled endless amounts of junk into the audience's head. Newton Minow's famous description of TV as a "vast wasteland" actually occurred in 1961 when he was jumping the gun just a bit, but the reason it resonated was because it quickly came to seem prophetic in an era when Petticoat Junction and Gomer Pyle USMC could become massive hits.

And yet here was Sesame Street, obviously made with craft and care, directed at helping the most vulnerable members of society get something out of TV. It was greeted with fantastic reviews, and more than a little grousing about how adults didn't have anything this good to watch. Fortunately ...

2) Sesame Street solidified the place of PBS — which helped kick off the TV drama revolution

If the late ‘60s were a lousy time for good TV in the US, then the early ‘70s were one of the best eras. Alongside Sesame Street arrived such groundbreaking programs as All in the Family, Mary Tyler Moore, and M*A*S*H, with Saturday Night Live's debut right around the corner. But what's often forgotten about this era is that one of the foremost drivers of quality TV at the time was PBS, which imported some of the best British dramas of the era — particularly Upstairs Downstairs — and proved TV drama didn't have to be an endless series of episodic detective dramas.

But there's likely no PBS without PBS Kids, and there's probably no PBS Kids without Sesame Street and Mister Rogers' Neighborhood, the two shows that stood as children's programming cornerstones for decades. (The former continues to run, while new programming from the production company behind Neighborhood does well for the current PBS Kids.)

For all of the quality primetime programming PBS has offered over the years, the shorthand for the network still comes from its kids programming, and whenever threats are made to pull government funding from PBS, the quickest way to fight back against them is to suggest that those responsible are coming for Big Bird. The irony is that Sesame Street is mostly self-sufficient, thanks to merchandising fees and other revenue sources. But the platform it airs on continues to be available throughout the country because the show is seen almost as a public good. When NET became PBS, there was absolutely no guarantee it would catch hold. But it did, and Sesame Street was a big part of that.

3) The show focused on the education of preschool children, which wasn't a given at the time

Sesame Street's stated mission was to help preschool kids, often kids in the inner city who watched lots and lots of TV, learn the most basic things they would need to know — letters and numbers and colors and such. There have been thousands of studies indicating that the show was successful at this, that it was able to convey those concepts to kids who paid attention — and even those who half-paid attention.

The amount preschool kids could learn, as it turned out, was potentially huge

But what was most notable about the show's focus was that it was aimed at preschool children, who weren't necessarily seen as capable of absorbing much in the way of information. Instead, kids quickly proved they could learn how to count and what the letters were, thereby pushing kindergartens to teach more and more advanced concepts. The amount preschool kids could learn, as it turned out, was potentially huge. And Sesame Street was a big reason anyone came to know that.

Wrote Lisa Guernsey in Newsweek on the event of the show's 40th anniversary:

When people think of Sesame Street as the essence of educational television, what they don't realize is how much the show has educated the educators. "Before Sesame Street, kindergartens taught very little," says [Joan Ganz] Cooney, "and suddenly masses of children were coming in knowing letters and numbers." Independent research found that children who regularly watch Sesame Street gained more than nonviewers on tests of letter and number recognition, vocabulary and early math skills. One study, in 2001, revealed that the show's positive effects on reading and achievement lasted through high school.

4) Sesame Street helped television diversify

Yes, there were a handful of primetime programs in the ‘60s that opened up to racial minorities, but they tended to be gimmicky or call attention to their progressivism. Sesame Street was different. In the world of the show, people were diverse, because they were diverse in the world outside of television screens. The show has always done its level best to have characters — human or Muppet — who reflected any kids who might be watching at home, and in so doing, it opened television up to the kind of casual diversity many shows embrace today. The only other program of the era to be as significant in this regard was Star Trek.

But Sesame Street also diversified television's storytelling options. It could tackle big, difficult topics like death or the birth of a younger sibling, right up alongside silly pop culture parodies. It could do sketch comedy, and it could do musical numbers. Its characters could be one-joke, or they could have surprising pathos and depth. It reflected the world as children might have seen it, and that meant it reflected a bevy of emotional states and storytelling styles.

5) It became a shining example of the United States's soft power

Soft power, the ability to influence the world through cultural exports rather than military might, has been one of the US's chief advantages in recent decades. Even if the world doesn't always like us, it tends to like our movies and TV shows. And, to be sure, Hollywood movies were traveling the globe long before Sesame Street was a twinkle in somebody's eye.

But it's hard to miss how successful the Sesame Street format has been at crossing borders and adapting itself to other cultures. The parent program itself has visited other lands directly, but it's also spawned several different versions in countries from South Africa to Germany to China.

Sesame Street changes and morphs depending on whatever cultural context it's dropped into, but it remains recognizably the show that was created in 1969 — one whose characters have become international ambassadors of teaching kids to read and, yes, expressing the American ideal of turning just about any medium into a way of pacifying young ones.

Television is unquestionably a better medium because Sesame Street exists, but it's also possible the world itself is a better place. Not bad for a bunch of well-meaning educators and some puppets.