Tupac Shakur, known by his stage names 2Pac, Pac, and Makaveli, is regarded as one of the most iconic and influential rappers of all time.
What he brought to hip hop was a level of rawness and a poetic drive in the way he delivered his words.
He had a level of self-empowerment that made people want to listen to what he had to say.
Even today, you could fly anywhere and surely there'd be someone who knows of Tupac. Here's why.
1. He was a master storyteller
Tupac took a lot of early inspiration from the politically-charged music of Public Enemy and Ice Cube.
He also studied theatre as a teenager at the Baltimore School of Performing Arts, and was inspired by Shakespeare.
"[Shakespeare] wrote some of the rawest stories, man," he told the LA Times in 1995.
Tupac's ability to communicate what was going on around him was second to none. It wasn't necessarily about telling a story in the most intricate and detailed of ways, it was about making you feel like you were there seeing what he was seeing.
He also had a real complexity to him. There was a side of him that wanted to just let it all out and cut loose and not care about consequences.
On the other side was that social conscience, showing all the facets of what life was life in the ghetto as a young black male, telling stories that hadn't been heard, and speaking out for the black community.
Songs like Brenda's Got A Baby on his debut studio album, 2Pacalyse Now, highlight that.
It tells the story of a 12-year-old girl from the ghetto who has a baby and ends up slipping into drugs and prostitution and is eventually killed.
2. It's all in the samples
Tupac sampled a range of artists on his records, such as Herbie Hancock, Pink Floyd, Parliament, Joe Cocker, Public Enemy and Stevie Wonder.
Trapped, one of the hit singles from his first record, samples James Brown's The Spank.
Brown is one of the most sampled artists in hip hop, along with Curtis Mayfield. They were both powerful, strong figures for the black community.
It wasn't just a case of choosing a sample because it sounded good; artists and producers would often incorporate people and songs that meant something to them.
Depending on when you were born, you'll either recognise Bruce Hornsby and the Range's The Way It Is as the original, or from Tupac's posthumous hit Changes.
Hornsby's 1986 track addressed issues of poverty, classism, and racial segregation, all things that Tupac experienced firsthand growing up.
The upbeat sound of the chorus is at odds with Hornsby's somewhat defeatist lyrics, claiming "that's just the way it is, things'll never be the same".
But with Tupac's verses calling out racism, war, violence, drugs and police brutality thrust in between, Hornsby's words, re-sung by Talent, start to sound more authentic.
3. The power of his voice
Singers are able to use different parts of their body to produce different sounds.
For example the term "head voice" refers to a person singing high in pitch, and using the part of the voice that resonates from the head.
The "chest voice" range resonates from the chest area.
In the documentary Tupac Shakur: Thug Angel, one of Tupac's early producers, Greg "Shock G" Jacobs, talks about how rappers also project from different parts of their body.
"Slick Rick rhymed from the nasal palate, Nas from the back of his throat, and Pac from the pit of his stomach, which is where his power came from," he said.
Where Biggie Smalls would swing like a jazz horn player, Tupac took inspiration from powerful speakers like Martin Luther King and Malcolm X.
You can hear and feel the weight and the power of his voice, which made him sound 10 feet tall, when in real life he wasn't that big of a person.
4. Stacks, layers and husk
Another technique Tupac was known for was stacking or layering his vocals, which added another dimension of warmth and rawness to his voice.
This technique is often used by rappers to emphasise certain rhythms, words and phrases. Tupac does it on the track Dear Mama, from his 1995 album Me Against the World.
Stacking vocal lines is very difficult to pull off, if not done well it can disrupt the flow of intricate patterns and phrases can be hard to make out.
Listen to the lyrics "and even though I act crazy/I gotta thank the Lord that you made me". You can hear his voice transition from being quite full to quite husky as he hangs on the final words.
To nail the same rhythm and tone quality every single take is very challenging. But Tupac, who had studied jazz and poetry as well as theatre, had an incredible control of rhythm and was able to layer his vocals very effectively without compromising flow or cohesion.
5. The sense of urgency
In 1995, Tupac served a nine-month sentence on charges of sexual assault, something he strongly denied.
The period between his release from prison and his death almost a year later was very intense.
He came out of jail firing shots; he had a lot to say and made a huge amount of music in this time.
He dived into a world of gangster rap, formed a new group called Outlawz Immortalz and signed to the notorious record label Death Row Records.
In terms of his approach to production, he wasn't focused on the musicality of the songs. Instead he had a real urgency to make music.
You can hear this intensity and urgency in Tupac's delivery on tracks like Hail Mary, from his posthumous album 7 Day Theory.
The song took around 30 minutes to make, and was recorded in a few takes.
Tupac didn't feel the need to be spending time in the studio choosing the right beat or the right kick.
"We don't have time … we don't have the luxury to spend all of this time doing one song," he would say to his crew.
In October of 1996, Tupac was killed in a drive-by shooting in Las Vegas that still hasn't been solved. He was 25.