The new HBO film “King Richard” premiered on Friday and tells the story of Serena and Venus Williams and their father, Richard Williams. Arguably the two most well-known tennis stars ever, the film aims to shed light on their life before they burst onto the professional tennis scene as it centers around Richard and his coaching of his two daughters. 

Here are five things to know about the Williams sisters and their dad before seeing the film:

Humble Beginnings

Perhaps the most remarkable aspect of the Williams sisters’ story is their unorthodox beginnings in Compton, California. The unlikely setting for the origin of two of tennis’ greatest ever stars is intrinsic to the conversation surrounding them. 

Serena and Venus Williams were born to Richard Williams and Oracene Price -- Venus in 1980 and Serena in 1981. The two moved to Compton at a young age and began playing tennis by the age of four. 

The pair was coached primarily by their parents until they moved to West Palm Beach, Fla. to be coached by legendary tennis trainer Rick Macci. Their father eventually pulled them from the academy and continued to coach them at home. 

Their story is a far cry from the usual beginnings of tennis stars who attended elite academies. When asked about their unorthodox path, Serena is quoted as saying "Everyone does different things. I think for Venus and I, we just attempted a different road, and it worked for us." 

Home-Coached by Their Dad

Both the Williams sisters were famously coached primarily by their father for whom the film is named. Richard’s own history in the sport is unusual as he claimed to have been trained by a man named “Old Whiskey.” Richard decided he wanted his daughters to play tennis after watching Romanian tennis star Virginia Ruzici. Richard says he wrote an 85-page plan for the sisters and started training them at the age of 4. 

An Early Professional Start

Emblematic of their later success is the early entry the sisters had into professional tennis. Venus turned professional at the age of 14. She managed to win her first professional game against NCAA champion Shaun Stafford in the first round of her first tournament. In the second round, Venus lost to eventual tournament champion Arantxa Sánchez Vicario.

In Serena’s case, her parents waited until she turned 16 to allow her to compete in professional tournaments. Serena’s professional career started rockier than her older sister’s, as she lost badly in the first few tournaments she entered. Then, at a tournament in Chicago whilst ranked 304 in the world, she managed to upset No. 7 Mary Pierce and No. 4 Monica Selles. By doing this, she became the lowest-ranked tennis player to ever defeat two top-10 opponents in the same tournament. 

The Williams Sisters Rivalry

Along with being regarded as two of the greatest tennis players ever, Venus and Serena were often at their most enthralling as opponents. The two have met 31 times in professional tournaments, and Serena leads their head-to-head record with 19 wins to Venus’ 12. The two have also both spent time as the No. 1 female tennis player in the world, though Serena has had much longer periods at the top: Venus has been ranked No. 1 for a total of 11 weeks throughout her career whereas Serena has racked up 316 weeks on top. 

The pair is also the only women to ever face each other in four consecutive Grand Slam finals. The streak lasted from the 2002 French Open to the 2003 Australian Open, and Serena won all four of the matchups. 

Their Prowess as a Pair

The Williams’ achievements as doubles partners are historic but expected from two of the most dominant tennis stars of the Open Era. The two have won 22 titles along with 14 Grand Slam titles. They also won an impressive three Olympic gold medals as partners. 

They made history when they lifted their first Grand Slam title together when Venus was 18 years old and Serena just 17 years old. The sisters only gained momentum from there, and after winning the 2001 Australian Open, they completed not just a Career doubles Grand Slam but a Career doubles Golden Slam. This proved to be legendary, as they were the first-ever doubles partners to win a Career Golden Slam.