Music festivals have sealed their place in pop-culture history; they also continually spark future visions. Fifty years ago, in upstate New York, Woodstock's original 'Aquarian Exposition: three days of peace and music' and 400,000 turn-out created a defining experience that still dominates festival dreams. Woodstock's hippy spirit (captured in numerous images, films and songs) summoned the sense that the music festival could be life-changing; it's that promise of al fresco mass epiphany that still drives modern festival ideals, whether it's the Woodstock 50 event headlined by Jay-Z and Dead & Company this August, the epic showstoppers of California's Coachella (which marks its 20th anniversary this year), or the tropical fantasy through which 2017's Fyre Festival was marketed (versus its notorious meltdown, as depicted in Netflix and Hulu documentaries).

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In the 21st Century, seemingly myriad music festivals take place around the globe. In 2015, Billboard magazine reported that 32 million people attended at least one US music festival each year (that number is technically more than the entire population of Texas), with 14.7 million of those defined as 'millennials' (a young adult demographic particularly attractive to brand advertisers). The obvious assumption is that festivals have shifted from counter-culture to mainstream commercialism; steep ticket prices make most festivals a 'luxury' event (even if the experience is very different) and heavy marketing feels ubiquitous, with corporations and social media 'influencers' cashing in on festival themes - even the Fyre festival docs feel like a shrewdly skewed kind of marketing.

Writing in The New Yorker in 2016, Carrie Battan observed of Coachella: "From a distance, it looks less like a haven of free-spiritedness than a catwalk of people who have decided that free-spiritedness looks good on them" - although she also argued that there might be something "radical" about the apolitical simplicity of that modern experience.

Born free?

It's also worth noting that Woodstock, and its British kindred spirit, the Isle of Wight Festival (now revived for the 21st Century), were originally paid-ticket events (the 'free' part came when crowds exceeded expectations); Woodstock headliner Jimi Hendrix earned $18,000 for his closing-hours set. Woodstock may have irked the establishment - on 18 August, 1969, The New York Times reported under the headline Nightmare In The Catskills ("What kind of culture is it that can produce so colossal a mess?" - though it conceded that "the great bulk of the freakish-looking intruders behaved astonishingly well"), but its "peace and music" ethos was deemed fragile. In December that same year, the Rolling Stones headlined a free concert at Altamont Speedway (documented in a new book by photographer Bill Owens); the event descended into violence involving Hells Angels who had been enlisted as 'security' - culminating in the death of black American teen Meredith Hunter.

At Coachella, we lost our virginity again - Daft Punk's Guy-Manuel De Homem-Christo

Somehow, a positive ideal endured in music festivals; it has almost transcended reality. The ultimate Woodstock anthem was arguably penned by a musical genius who wasn't even there: Joni Mitchell (her much-covered Woodstock rejoices: "We were half a million strong/ And everywhere there was song and celebration"). That nostalgic blend of 'peace and music' retains its power in contemporary scenes; take Lana Del Rey's woozy 2017 track Coachella - Woodstock In My Mind.

At the same time, modern festivals have been shaped by increasingly broad cultures and cutting-edge tech; the 1990s convergence of rock spectacle and rave dynamics proved a turning point. And through this all, artists and audiences still seek that 'life-changing' potential; after a triumphant Coachella set in 2006, Daft Punk's Guy-Manuel De Homem-Christo proclaimed: "At Coachella, we lost our virginity again."

If festivals represent the ultimate shared experience, that status is rapidly transformed through social media and broadcasting. Britain's historic Glastonbury festival (run by the Eavis family on their farmland since 1970) has since 1997 also been a flagship multi-channel highlight, progressively spanning TV, radio and digital media.

As the BBC's Head of Music TV Commissioning Jan Younghusband explains: "We want to give people the best seat in the house, so that they can feel part of a national event, even if they can't physically attend. The great thing about our coverage is that people can experience the atmosphere of the festival without leaving their homes." Festival crowds are still driven by a sense of FOMO (fear of missing out), though, and it's clear that even expansive coverage can only capture a hint of what it's like to actually be at an event as big as Glasto or Coachella, with the prime-time focus on commercial acts.

Still, in the modern age, broader audiences than ever can channel-surf through at least a taster of multi-stage programming, and Coachella statement pieces feel primed to go viral - whether it's a holographic Tupac Shakur's posthumous performance in 2012, or Beyoncé's massive 2018 headliner (melding politics with costumes by couture house Balmain).

At the opposite end of the scale, it's hard to imagine Fyre Festival gaining quite the same infamy if it wasn't for social media posts (in particular, a meme of a processed-cheese slice in a Styrofoam box - apparently the 'gourmet food' promised by the organisers). You might also wonder how controversial events such as Woodstock '99 (broadcast by MTV, but also involving much darker reports including sexual violence and arson) might have lingered in our public consciousness had social media been as prevalent then.

Keeping it real

The authenticity of music festival heritage (and its deep-rooted ideals) is arguably something worth preserving. As Glastonbury's Emily Eavis told The Guardian newspaper in 2013: "I spend a lot of time saying no to people. No to corporate sponsorship, no to brands or things that aren't in keeping with our ethos. If I see things that have got through... then I flip."

At their best, music festivals remain a rite of passage, and a creative playground where new expressions can be conceived. Celebrated DJ and record-label founder Gilles Peterson recalls his youthful trips to the Montreux Jazz Festival (where he'd watch other music lovers without being able to afford a ticket himself), and to Nice Jazz Festival ("All my mates from London would go there like a pilgrimage; it was this amazing, exotic, international world of great music"). Peterson would go on to curate his own hugely successful stage at Montreux in the 1990s, and in 2006, he co-founded the acclaimed independent Worldwide Festival in Sète, France.

"The British bring the club culture and the decadence, and that blends with the local energy," Peterson tells me. "You can't just go somewhere and bulldoze your way in; we make sure that we get to know the local communities and businesses, and we try to create events where exceptional things can happen." That approach extends to Worldwide's latest 'family gathering', the We Out Here jazz festival in Britain this August. "It's about connecting scenes and the world in one place, and we can have a grand party," says Peterson.

Globe trotting

Music festivals increasingly draw Western audiences to global destinations, and another glaring aspect of the Fyre Festival fiasco was its exoticism: peddling festival-goers a luxury island 'paradise' (which transpired to be anything but), and leaving local businesses and contractors unpaid. Bahamian journalist Ava Turnquest made a serious point in the Hulu doc Fyre Fraud about "The culture of exclusive resorts, this ultra-luxe lifestyle in an environment where there is so much poverty - there is a level of collusion and pay for play and kickbacks involved."

The flipside of this is modern music festivals as a platform for international talent. For instance, the modern festivals scene across the African continent encompasses major destinations such as Lake Malawi's Lake of Stars (involving African and European acts), new events like Lagos's Homecoming Festival (including Nigerian superstars such as Wizkid alongside British grime and rap artists), and acclaimed independent festivals including Zanzibar's Sauti za Busara (meaning 'Sounds of Wisdom'): a live annual event that has run in the historic hub of Stone Town since 2004 (only taking a break in 2016 due to political uncertainties and ensuing lack of funding).

"The scope of the festival has grown and evolved steadily over the years, to the extent it now showcases music from across the African Continent and diaspora," explains festival director Yusuf Mahmoud. "Local and regional musicians are inspired by the visiting artists and vice versa; local and international audiences enjoy performances shoulder to shoulder, in a safe, peaceful and positive environment where few opportunities otherwise exist for such intercultural interaction and exchange."

Mahmoud argues that music festivals do fundamentally have a life-changing impact, and he credits the dedication of SzB's local crew: "Most return year on year, whereby their confidence and abilities have developed to the extent we now have a world-class event with excellent technical production," he says. "It is fulfilling to know the festival brings social, cultural and other benefits for the region by providing jobs, building skills and livelihoods, promoting good-news media stories for Africa and boosting Zanzibar's grassroots economy, whilst also keeping local music traditions alive and moving forwards."

Another music festival with an enduringly global ethos is the brilliantly convivial Womad (World of Music and Dance), co-founded by musician Peter Gabriel in 1980, and now running several international editions in addition to its annual British event in July. When I catch up with Womad festival director Chris Smith, he has just returned from Womad Chile; soon after our conversation, Womad NZ went ahead despite opening on the day of the tragic massacre at Christchurch mosque: a symbol of mass togetherness in defiance of bigotry.

When you put on festivals, you're forming a mini-society with a common goal... it takes a unique sense of community - Chris Smith

Smith is in no doubt about why music festivals have an enduring place in pop culture. He notes that they're "escape, total immersion" but adds that: "When you put on festivals, you're forming a mini-society with a common goal: to make an amazing cultural event happen. It takes a unique sense of community, which maybe modern life has less of."

In the clamorous modern festivals scene, there's increasing pressure to deliver that 'life-changing' sensation; while big-budget events might be able to secure exclusive music acts, many others now diversify, blending sport, cuisine, comedy, or (in the case of Britain's Bluedot festival) science into the mix. Festival tech is also growing smarter, with growing use of on-site apps and wristbands containing RFID (radio-frequency identification) chips for admission and payment; these might make our festival-going experience more convenient, but they also collect useful data about our habits - who we plan to see, where we actually go, what we buy - that could be used to shape future fest line-ups and layouts, and it lends an undeniably sinister edge to the 'personalised' good times.

Even so, the human element remains vital; music festivals represent a febrile ground much closer to grassroots than databanks, and a programme designed by a passionate, clued-up curator is hard to simply synthesise. For any generation, they're unlike any other place on earth: a site liberated from everyday rules, where we might bond with strangers and stumble across new sounds and sensations; the location for a lost weekend, as well as that 'once-in-a-lifetime' promise that keeps us coming back for double, triple, countless encores.

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