Discovering Joni Mitchell is something that I did alone. Sixteen years ago this summer I was midway through that transition period between college and university. Working in a part-time job after school, I often found myself listening to music on my headphones in relative isolation. Over that summer, I developed a love for Joni Mitchell's Blue, an album that was twice my age at the time. Blue stood out to me as a key example of what it meant for a musician to make music that was full of passion and that age-old misnomer, authenticity. To me, Mitchell seemed to epitomise the legendary 1960s Californian hippy-folk idiom that felt like a relic from a lifetime ago. There was something curious and exotic about her image, yet time has shown that to be a misconception - a symptom of a culture that can't help pigeon-holing women artists.

For anyone looking to discover Joni Mitchell's work, Blue should be the starting point. From there one can work backwards or forwards, but Blue is quite literally the blueprint of her life's work. It also happens to be her most famous record and recently came third in Rolling Stone magazine's list of the 500 Greatest Albums of All Time.

Now, sixteen years later, I see Mitchell in much the same way as her fans and critics do, which is to say that I recognise her as one of the most authentic and influential musicians of the twentieth century. Mitchell has never not been acclaimed, but the consolidation of her status in recent decades attests to her music's staying power across generations. The fact that her music still resonates deeply with both young children and those who were there to witness her rise in the 1960s is proof of the timeless quality of those songs, whose words and messages translate on a fundamental human level.

Connecting with Blue as I did at a relatively young age has always felt like a very lucky strike. In its stunning intimacy, it illuminates the complex world of adult relationships which, as a teenager, felt alien to me. Even now in my mid-thirties, perhaps I'm not much wiser. Maybe that's why Blue continues to resonate. Its mark is permanent for anyone who ever sought refuge in music's potential to teach and inspire. If you catch its drift, it'll never leave you.

Mitchell was aware of music's ability to make permanent marks. The title track opens with the line "Songs are like tattoos." And like a tattoo, the album sticks and endures; to the listener, it symbolises a deeply personal series of emotions that have become interwoven with its constituent songs. Blue is amongst a small handful of albums that still accompany and remain important to me, despite the passing of decades. The sheer effortlessness of its presentation and sequencing belies hidden complexities. I never tire of hearing it. At this point in my life its ten songs have become more like hymns, or campfire songs that I can recite subconsciously. For me, and for millions of people over the last half century, it has embodied that indelible mark "underneath the skin - an empty space to fill in."

Blue was released in June 1971 and this week marks its fiftieth anniversary. It's a moment that deserves reflection and a consideration of how - and why - it has touched so many lives, beyond the obvious recognition of its reputation as a breakthrough work in the singer-songwriter field. In the last two decades in particular (and with increasing regularity), Mitchell has found herself the subject of constant tributes, honours and symposiums. Often these performances sound nothing like Mitchell's originals, demonstrating the traversal of her music across cultural and social boundaries. To witness these performances of her work by other artists is to unearth the original source material - like annotated notes that run alongside Shakespeare's sonnets - and yet Mitchell has been the first to claim that people often dig through her work looking for hidden meaning where there might not be any. In other hands, her music signals something of a leveller, both as a standard and daunting benchmark for so many songwriters to measure themselves by.

Mitchell has often said that the listener must see themselves in her songs, otherwise they would struggle to find any value in them. In order to enable her audience to do that, however, she had to "strike against her own nerves." This feels particularly true of Blue, a record that consistently pushes itself to plumb the dark places of the human psyche. Part of why Mitchell is so loved is that she dared to go there and share her pain with the world.

Blue is legendary for its honesty and commitment to raw truth-telling. It shocked listeners at the time for its "emotional nakedness," laying bare the despair that can dwell in the human heart over a lifetime. Mitchell always depicts that honesty through her own experiences, once claiming that she was privy to this "weird sort of worshipping" and a level of attention that made her very uneasy. It was an honesty that she sought out - indeed, demanded of herself - in order to let those listeners know who they were worshipping. That communication with an audience is commonplace now, but before Mitchell committed to making it her life's work, it had never really been explored - at least not to the places she took it.

The songs on Blue feel deceptively straightforward. There is very little in the instrumentation to distract you from that voice and those words. Whether by dulcimer, guitar or piano, Mitchell's instruments never overplay their hand. Her open-tunings might be unfamiliar yet they're also spacious and inviting, the canvas on which her words sing and draw the listener's focus. Her lyrics are their own kind of poetry, squeezed from the subconscious, while her vocals, effortlessly tumbling and soaring with the grace of a gymnast, range from a soft whisper to a glorious declaration, drawn out until every last slow breath is exercised.

The album opens with All I Want, breaking out of the gate with an unhurried, steady canter. Mitchell's homespun lyrics possess an irresistible simplicity and, whilst revelling in warm colours (rhyming "shampoo" and "renew" in the same breath as "sweater" and "letter"), she takes care to place one of her darkest and most devastating lines right before the song shifts gear: "Oh, I love you...when I forget about me."

My Old Man follows, a piano-led paean describing the conflicting emotions of a relationship paradoxically frustrated and yet stimulated by distance. "But when he's gone, me and them lonesome blues collide; the bed's too big, the frying pan's too wide," sings Mitchell. A live BBC performance from the time shows Mitchell in joyous rapture, as though safe in the gentle buoy of her own vocal melody, eyes closed and beaming from ear to ear.

Later on the album, River hints at a possible worst-case outcome of those oscillating emotions described on My Old Man. Mitchell finds herself bereft, alone and longing for nothing more than a quick escape from heartache and her own "selfish sadness." Much of Blue is spent traversing sadness; soul-searching, introversion, and yet a thirst for emotional catharsis that can only be made possible through navigating such inwardness. Elsewhere, Mitchell spends much time on Blue gravitating towards something, restlessly searching. Yet this yearning is often countered by a pulling back towards familiarity and a deep love for California, particularly in phases of homesickness and travelling on the road. The opening lines of the album set the tone: "I am on a lonely road and I am travelling, travelling..."

Both Carey and California feel cut from the same cloth in this respect, bracketing the sombre title-track at the halfway point of the album. Both songs chronicle excursions across Europe, but undertaken as a means of escaping something back home. Mitchell jets off to France and Spain, parties down red dirt roads and dances around a fishing village with a cave-dwelling hippie in Crete. These journeys chart experiential learning with a youthful naivety, yet ultimately Mitchell finds herself longing to return to the Californian cradle that played host to her own personal and professional revolution. In the former, she misses her clean white linen and her fancy French cologne. In the latter, she serenades California itself, describing the song's namesake as perhaps her most steadfast, unyielding love. For Mitchell, it is California who might just fulfil her plea to "take me as I am," albeit while "strung out on another man."

Across Blue, Mitchell expanded her vocal palette further than before as her control became sharper, ever more resonant, ever more radiant. As her voice refined, so too did her character studies, gradually shifting the gaze from herself to the social scene was emerged in. Mitchell would continue to examine her own emotions with an almost forensic observation across a glorious run of albums in the 1970s. "Everything comes and goes; pleasure moves on too early and trouble leaves too slow," she wrote three years later on 1974's Court & Spark. Here she demonstrates perfectly what so much of her best music does, which is say a lot in so few words. Mitchell is of course referring to the courtship period of a romance as all too fleeting and the subsequent breakup as something that seems to linger despite our best efforts to move on and begin anew. These words also demonstrate the feeling of being caught in limbo between two emotional states: an internal voyage across uncharted territory. That limbo stage often doesn't last long, but time and time again Mitchell draws out and suspends her focus, daring to hold both happiness and sadness in the same hand.

One of Mitchell's earliest compositions spoke of an "urge for going," to leave behind troubles and seek out new possibilities. Like the shifting seasons described in that song, Mitchell wouldn't stay tangled up in her Blue period for long. In response to the newfound (and unwanted) global fame it brought, she purchased a property in British Columbia immediately after and spent a year in isolation living off the land. She released the underrated For The Roses in 1972 and followed that with a bold and confident return to the city of the fallen angels on the gorgeous Court & Spark.

Blue concludes its ten-song run with The Last Time I Saw Richard in which Mitchell describes the elder protagonist as someone who has lost his spark after a string of failed relationships. The younger Mitchell urges him to pull himself together in an attempt to “get him back on his feet” because “love can be so sweet.” In the end Richard gets married whilst Mitchell settles for ambiguity, “hiding behind bottles in dark cafés,” perhaps hardened by her experiences. Mitchell’s crux here hides in plain sight: the notion that while some people thrive on the thrill and spark of new romantic love, others are destined to define their experience of love by the exquisite pain of having lost it. So often in Mitchell’s songs, the final destination is arrived at with a bit lip, furrowed brow and a question mark.

Blue ends suggesting that nothing is certain. Love — indeed, “everything” — comes and goes. Perhaps, other than the undeniable showcase of Mitchell’s talent, it’s these painful, universal truths and the bravery to tell them that sets the album apart. For most of her longtime fans, Blue has lingered on for decades, much like the “sigh” that Mitchell describes in a beach shell on the title track — a “foggy lullaby,” accumulating resonance and growing louder with each passing year. Its power lies not in what we might project onto it as a work of art, or what we might infer about the emotional capacity of the musician who created it, but one which reflects — like a mirror — all the complexities about who we are. Mitchell, the self-professed woman of heart and mind, offered in Blue a roadmap to help guide many along life’s path.