Which genre of music allows you to play the same notes night after night but differently each time? Why, jazz of course, to put it simply.

As Esplanade’s jazz appreciation month swings into action this July, the spirit of spontaneity, creative expression, and innovation descends upon us through the swinging rhythms, soulful improvisations and infectious grooves of Singapore's jazz cats.

Here are 12 fun facts that will not only surprise you but also give you something to toot your horn about.

If you haven't had the chance to encounter its myriad forms and styles, tune in to Jazz in July and #givejazzachance.

1. Jazz actually started out as pop.

While most people today consider it a genre of the elite and well-established, its roots are quite the opposite. A combination of ragtime, European chamber elements, marching band music and blues, jazz exploded into the American music scene in the 1920s and became the most popular music form of the era. Need proof? Take it from the writer F. Scott Fitzgerald, credited with popularising the term "the Jazz Age" and whose novel, The Great Gatsby (1925), epitomised this decadent, tumultuous period.

2. No one really knows how the word "jazz" came about.

In fact, since it was originally a slang word, it was sometimes spelt as “jas”, “jass”, “jaz”, even “jasz”. One of the most popular theories is that it was first used as a baseball term to mean verve, vim, and fighting spirit; another suggests that it was derived from the African slang word “gism” or “jism”, which had sexual connotations.

3. Jazz musicians “turn off” a part of their brains during improvisation.

Here's some food for thought. According to a study conducted by two professors from John Hopkins University, when jazz musicians improvise, their brains turn off the dorsolateral prefrontal and lateral orbital regions linked to self-censoring, inhibition and introspection, and turn on the medial prefrontal cortex—the part of the brain that lets self-expression flow.

Findings also show activity in the language areas of the brain when two musicians are having a "musical conversation".

Even if you’re not a jazz musician, listening to jazz stimulates your mind since the brain mimics the pulsating rhythms of improvisation—it’s kind of like a “monkey see, monkey do” situation. If you’re looking for new ways to spur your child’s creativity and critical thinking, jazz is one way to go.

4. A jazz performance is full of secret hand and body signals.

Secret signals? Say what?! With so many things happening on stage, musicians communicate with each other non-verbally. They usually cue the end of their solos with nods, or the end of the piece by pointing their fingers at their heads (meaning it’s time to play the “head” – the main theme or original melody of a song). The next time you’re at a jazz performance, see if you can spot any "sign language"!

5. The piano trio is the most common jazz configuration.

It has often been said to represent the essence of jazz in the most condensed yet effective way. A piano trio takes full advantage of swing, interaction, and dynamics.

6. While many consider jazz a relic, it is well on its way to making a glorious comeback in mainstream music.

Musicians such as Kendrick Lamar, Flying Lotus, Grammy award winners Robert Glasper and Esperanza Spalding, among others, are bringing it back through their own musical fusions that range from Jazz Age-inspired “hot jazz”, hip-hop-infused hybrids, to world jazz. Did you know that Flying Lotus, an experimental multi-genre producer, electronic musician, DJ and rapper, is the grand-nephew of jazz legend John Coltrane?

7. Jazz is one of the most hybrid forms of music.

Because it is free-spirited and spontaneous, jazz has come a long way since it was first introduced. It has spawned different styles such as bebop, big band, swing, Latin jazz, dixieland, gypsy jazz, and bossa nova jazz, and also encompasses contemporary sub-genres including free jazz, acid jazz, and soul jazz.

8. Jazz and Indian classical music share more in common than you think.

Like jazz, Indian classical music—defined by its two systems, hindustani and carnatic—allows for extended improvisations and dazzling displays of melodic and rhythmic virtuosity. Both genres have pulse-oriented rhythms and modes.

In fact, saxophonist John Coltrane and guitarist John Mclaughlin are just some of the many jazz musicians who were heavily influenced by it. The former was drawn to hindustani music because of revered sitar player Ravi Shankar (credited for single-handedly popularising Indian music in the West), while the latter was influenced by carnatic music, as evidenced by his music groups The Mahavishnu Orchestra and Shakti (which featured big names, such as carnatic violinist L. Shankar, tabla player Zakir Hussain, mridangam player R. Raghavan, and ghatam player T. H. "Vikku" Vinayakram).

9. If not for jazz, dance styles such as the Charleston, black bottom, Argentine tango, and the trot would not have made their way into the dance halls of America.

The birth of jazz gave rise to public music and dance halls, which brought social dancing up a notch from the classic waltz and tango. Inspired by the highly expressive nature of the music, new dance styles were constantly created or introduced.

10.Jazz boosts your creativity and productivity at work, relieves stress, and increases your immunity.

Did you know that listening to jazz activates theta brain waves (4-8 hertz), the most highly creative brain wave? They inspire new insights and solutions to unresolved problems—or to put it plainly, they bring about “eureka!” moments.

Jazz is also just as effective at reducing anxiety as a massage and, according to a Time magazine article, has the same restorative effect as total silence. Listening to it for 30 minutes can also improve your immunoglobulin A (IgA) levels, which prevents viral and bacterial infections!

11.Before the saxophone became synonymous with the image of the jazz musician, its distant cousin, the clarinet, was a much more popular instrument.

The clarinet was once the dominant instrument in jazz; it defined the sound of the swing era and was known by its nickname, ‘licorice stick’. When the saxophone first appeared, many jazz musicians were adverse to it.

12. The term "hipster" was derived from one of the terms unique to jazz.

You’ve heard of the term “jazz cats”, which refers to jazz musicians. But before they adopted the nickname, did you know that they called each other “alligators”, or “gate” for short? In fact, this is just one of many terms that are unique to jazz. “Hep” was a popular term in the 1930s used to describe someone who is cool and knowledgeable: a hepster/hep cat. The term “hipster” was derived from this.

Some other interesting jazz terms:

Blow – to improvise a piece or play an instrument

Boogie – an early style of piano blues

Chops – excellent musical skill

Lick – a term for phrase or solo

Scat – improvising the words of a song with wordless syllables; made famous by Ella Fitzgerald

Can you talk the jazz talk? Take this quiz and see how hip you are.