You may not know their faces, but you know their voices.
They're voice actors. And if you're like me, they shaped your early years: I grew up on Looney Tunes. Mel Blanc was a wizard - I was shocked as a kid when my dad told me Blanc voiced nearly every single character on screen. I woke up at 6am on Sundays to watch Count Duckula (when it aired in the US). I had my parents tape Japanese anime (which was not as popular in the West as it is today) on our VCR every weekday morning as I headed off to school. Those characters' voices were the soundtrack to my childhood.
Fast forward some 20 years later, and it's clear I'm not alone.
Fan conventions like Comic-Con, which celebrate cartoons old and new, now pop up on every continent, and some performers who voice popular characters have huge followings on social media platforms like Twitter.
It's a pretty anonymous profession - or it used to be - Rob Paulsen
Voice actors have power. Whether you hear them through the voice-activated assistant in your kitchen, the navigation system in your car, a cartoon you watch with your child, or a video game you play alone, their voices inject humanity into the experience.
And while voice actors at the top of the industry can earn salaries as high as film stars, their real influence is more profound. They conjure an emotional connection and bond between you and the work or product.
So what's it like to be one - and how have changes in technology and the industry shaped the career?
The growing power of voice actors
"It's a pretty anonymous profession - or it used to be," says Rob Paulsen. He's a voice actor who's starred in Animaniacs, Pinky and the Brain, and both the '80s and 2010s version of Teenage Mutant Ninja Turtles. He also runs a regular podcast on the voice acting industry.
Now? The once-invisible performers lead panels in packed convention centres at events the world over, and can command massive social media followings. For example, Tara Strong has over 350,000 Twitter followers - she's starred in animations like The Fairly OddParents, Rugrats, The Powerpuff Girls, as well as the Final Fantasy video game series.
"It's really, really hard to break in," says Strong. "You have to know that's all you want to do. You need to make sure to have a lot of acting training: scene study, improv classes, and singing lessons to learn what your instrument can do." Voice actors mention meeting fans at conventions who want to become voice actors themselves.
She also says "it doesn't matter what you look like - you get to play all kinds of characters."
And while many voice actors have done plenty of on-camera, sometimes voice acting opens even more doors.
"I didn't have to worry about my ethnicity in terms of getting cast, or physicality: I'm extremely short. I'm under five feet," says Stephanie Sheh. She's an actor whose voice has appeared in English dubs of nearly 300 Japanese anime series. That includes the most recent English dub of the iconic magical girl superhero show, Sailor Moon, as well as the 2014 reboot, Sailor Moon Crystal. "I'm very specific physically, so that really limits a lot of roles that you're up for as an actor."
I didn't have to worry about my ethnicity in terms of getting cast, or physicality: I'm extremely short. I'm under five feet – Sheh
But many of them began careers as actors, and fell into voice acting - and they caution fans who want to follow in their footsteps.
"A misconception is that it's easy [to break into] because it's just your voice," says Sheh. "So you have a lot of non-actors trying to pursue it."
It's crucial for aspiring voice actors to perfect their actual acting skill, to take smaller gigs, and be willing to do less glamourous work such as corporate videos as they work their way up, according to the professionals. And even in an age of flashy video games, talking robots and films with computer-generated imagery, lots of clients still need a voice artist.
"Honestly, anywhere you hear a voice? It was probably created by a human," says Tara Platt, who wrote a book about the career with fellow voice actor Yuri Lowenthal. "Your vocal signature is like your vocal fingerprint. There's something very human about that."
The rise of anime
To get a sense of the scale of the voice acting industry, we need to look at Japan: according to the Association of Japanese Animations, the anime industry set a record in 2016 when it generated revenues of ¥2.01 trillion ($17.7 billion). That total comes from TV, film, internet distribution and merchandising - all driven by overseas sales, which made up the majority of revenue.
All that popularity overseas means more opportunities for actors, even outside Japan. They're needed for dubbing: that's when actors take a translated script and dub over the characters' speech in a film or show into the local language with their own performance. Some actors who dub Japanese shows started out as fans.
"I did come from fandom," says Sheh. Being a fan, "I was a little bit more well-versed in the material, or the tropes, or what they were trying to get at."
Becoming a seiyuu (voice actor) in Japan, like in other countries, requires formal training. In Japan, there are nearly 50 academies specifically for aspiring seiyuu. The Tokyo School of Anime is one of them.
Around five years ago the video game industry started hiring more voice actors, which has increased demand, says Hironori Kagawa, a voice acting teacher at the school.
The institution offers several academic programmes for students who want to work in the anime industry, from illustration to sound engineering. The voice programme offers five majors and currently has 100 enrolled students. Many overseas students from the likes of China, Hong Kong, Korea, Malaysia, India and Canada are enrolled, too. All classes are given in Japanese.
It takes one to five years to become a professional anime voice actor
Students on the voice acting course take 15 classes a week for 90 minutes apiece, focusing on breathing, enunciation, learning how to work the mic, and even dancing and singing to develop a good ear and sense of rhythm.
Yui Fukushima says she was inspired to become a voice actor by watching Yo-Kai Watch, an anime that's a mix of Ghostbusters and Pokémon that took Japan by storm a couple of years ago. She especially looks up to Aya Endou, a voice actor who played a main role in the series, but also several of the show's colourful monsters.
"I was so surprised that voice actors make a lot of different kinds of voices in front of the mic - it was a big shock," she says. Her dream? "In the credits, I want to see my name for not just one character - I want it next to two or three characters."
The field is fiercely competitive. On average, Kagawa says it takes one to five years to become a professional anime voice actor - those years are spent honing the craft, as well as taking gigs like TV adverts or radio spots.
Winning roles in globally-recognised franchises like Sailor Moon takes years of experience, hard work and hours spent performing much smaller roles.
And there are a lot of other voice work gigs out there: TV adverts, corporate training videos, public transportation announcement systems, YouTube explainers, audiobooks, podcasts. Even digital voice assistants like Siri and Alexa, in their many languages and dialects, require human voice actors to supply all the audio.
Still, the bulk of voice work is in the entertainment industry. A 2017 report from Voices.com, a Canadian company that connects voice talent to clients, found that 53% of the total global voice work is in animation.
Honestly, anywhere you hear a voice? It was probably created by a human – Tara Platt
"Most commonly, people think of radio and television commercials because that's what the origin and genesis of the industry is," says Voices.com CEO David Ciccarelli. "But nowadays that accounts for about 10% of the market."
There's no shortage of people looking to make it. Voices.com alone has 400,000 registered users, with over 100 dialects and languages represented and 4,000 jobs posted a month.
But many of today's top voice actors say they didn't pursue voice acting specifically.
A common theme among voice actors is that they identify as actors first and foremost.
"That's what I tell people: come on out here [to Los Angeles], there's plenty of room," Paulsen says. "Be a voice actor. But it's small 'v', large 'a'. It's about acting."
That's a common refrain among nearly all voice actors: "The acting element always trumps the voice element," Sheh says.
There's also a reason why students at places like the Tokyo School of Anime learn singing and dancing - it's all part of performing. "You'll never see a voice actor standing completely still behind the mic," Strong says. "They're moving their arms and getting into it."
And voice actors may soon have to bring all that gesticulating into other gigs besides the recording booth for cartoons.
Video games turning cinematic
Video games have started to generate profits that rival Hollywood blockbusters. That, alongside the rising popularity of anime, means more jobs for more voice actors.
As the budgets have increased, the technology used in these games has become more sophisticated and storytelling more complex, so there's been an increased demand for voice work to bring game characters to life.
"As graphics have improved, so has the desire for more believable and meaningful performances from voice actors," says Roger Altizer, associate director of the University of Utah's entertainment arts and engineering programme. "While it is more expensive to have voice actors in games than not, players have come to expect it as a staple. This may be why famous voice actors have huge fan followings."
Tara Platt and Yuri Lowenthal point out that more video games are using performance-capture technology: which means voice actors' movements and physical actions are also recorded and digitally recreated in the game.
They keep increasing the amount of dialogue and the branching possibilities that a player can get into – Yuri Lowenthal
"For us, it's a return to theatre," Lowenthal says. "A lot of us started in theatre. And then for a long time we're in the [voice recording] booth, where you don't use your body and face as much. Now it's come full circle."
It's a far cry from when games first started hiring voice actors, when they were simply expected to do dozens of takes of throat-burning shrieks, groans and other death sounds to capture their characters' untimely demise.
But now? Lowenthal recalls a game he recently worked on that required 60,000 lines of real dialogue.
"With technology, the more information they can put on a disc or in a cartridge, the more performance they can pack into there," he says. "And now with the kinds of stories they're telling, they keep increasing the amount of dialogue and the branching possibilities that a player can get into."
As Platt says, as a voice actor who's worked in games, "you're filling out the world."
The power of the voice
Whether it's out of a cartoon character or out of an iPhone's Siri, hearing a human voice elicits a powerful response within us.
"Adding a human voice to digital assistants can act as a double-edged sword," says Rhonda Hadi, associate professor of marketing at the University of Oxford's Saïd Business School.
"On the one hand, consumers generally respond more positively to human voices, and tend to converse with voice-activated assistants in a more natural way than they would with robotic voices. However, human voices also lead consumers to anticipate high levels of understanding and empathy from digital assistants. When the assistants fall short - for example, not understanding what the consumer says or not providing an adequate response - this expectancy violation leaves consumers feeling more disappointed."
There's a responsibility. We associate a brand with a particular voice – David Ciccarelli
That goes for technology like video games, too: "Poor voice acting will break immersion far more quickly than bad graphics," says the University of Utah's Altizer.
And the same danger even rings true in the corporate world. "When they do a project, they become that audio ambassador - they become the voice of that company," says Voices.com's Ciccarelli. "There's a responsibility. We associate a brand with a particular voice."
But for many voice actors, they're well aware of the responsibility - and well aware of the very real, deep bond they develop with their audiences, too.
Paulsen speaks about meeting fans at conventions who say Ninja Turtles got them through their parents' divorce, or the Iraq vet whose fallen comrade loved Pinky and the Brain. "I never in a million years would have known that, ever."
It even affects voice actors themselves when they meet voices from their own childhoods, like when Tara Strong says she sang in The Little Mermaid 2 with Jodi Benson, the original Ariel.
"I burst into tears when I met her," Strong says.
To be sure, each work is the product of multiple talents, from animators to writers to musicians and more. But there's something about voices people can't seem to forget.
"When it's done correctly, it's the best of all worlds," Paulsen says. "It connects with people on a deep level, it gets them through difficult circumstances, it reminds them of their childhood, they're able to share it with their own children. It never gets old."
It seems that, regardless of technological advances and complications in industries, the power of the human voice holds strong.
"What makes voice unique is that it is genuinely human," Ciccrallei says. "It's not an extension of yourself. It is yourself."
Bryan Lufkin is BBC Capital's features writer. Follow him on Twitter @bryan_lufkin.
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