The Demon Slayer story takes place in Taichō era Japan, where a secret society, known as the Demon Slayer Crops, has been waging a secret war against the Demons for centuries. The Demons are former humans who were turned into demons by Muzan Kibutsuji injecting them with his own blood, and feed on humans and possess supernatural abilities such as super strength, powers that demons can obtain called "Blood Demon Art" and regeneration. Demons can be killed by weapons made from an alloy, known as Nichirin or exposed to sunlight. On the other hand, the Demon Slayers are entirely human. However, they employ special elemental breathing techniques known as "Breathing Styles", which granted them superhuman strength and increased resistance, helping them fight against demons. Then strongest Demon Slayers are known as the Hashira, and gain this rank through killing a member of the Twelve Kizuki (the twelve strongest demons under Muzan) or killing fifty demons after ranking up multiple times.
The elements of the Breathing Styles are
1. Sun Breathing. It's the first Breathing Styles in the world and it's known and taught by the Kamado family, and it's also known as "Hinokami Kagura" (lit. Dance of the Fire God). The current successor is Tanjiro Kamado. The user will receive the Hanafuda Earrings to symbolise as the Sun Breathing user and the Breathing Style has 13 forms.
2. Water Breathing. It's one of the main five Breathing Styles directly derived from Sun Breathing. It's the most uses Breathing Styles technique, because it's the easiest Breathing Styles to learn for beginners. The Cultivator is Sakonji Urokodaki. The Hashira of Water Breathing is currently Giyu Tomioka and there's a lot of Demon Slayers who using this technique, for example Tanjiro Kamado, Murata and etc. The Water Breathing Style has 10 techniques with an additional form, created by Giyu Tomioka.
3. Flame Breathing. It's one of the five main Breathing Styles derived directly from Sun Breathing. It's users is the Rengoku's family and Mitsuri Kanroji (formerly). The Hashira is Kyojuro Rengoku. The Flame Breathing Style has 9 technique in total, with six known forms. Among these, the "Ninth Form : Rengoku" is an "Esoteric Art" exclusive to the Rengoku family.
4. Thunder Breathing. It's one of the five main Breathing Styles derived directly from Sun Breathing. The Cultivator is Jigoro Kuwajima. The users are Zenitsu Agatsuma and Kaigaku, but Zenitsu can only performed the "First Form : Thunderclap and Flash" so he developed a Seventh Form to level up against Kaigaku, his former senior who had became the Upper Ranks 6 of the Twelve Kizuki. The Thunder Breathing Style has 6 standard forms in total.
5. Stone Breathing. It's one of the five main Breathing Styles derived from Sun Breathing. The only user of the Breathing Style is also the Stone Hashira, Gyomei Himejima. It has only 5 forms.
6. Wind Breathing. It's one of the five Breathing Styles derived directly from Sun Breathing. There're 2 users of the Wind Breathing Style, they're Sanemi Shinazugawa, the Wind Hashira and Masachika Kumeno. The Wind Breathing Style has 9 forms.
7. Moon Breathing. It's a Breathing Style derived directly from Sun Breathing. The user of it is Kokushibo, a former Demon Slayer, now he's a demon holding the Upper Rank 1 spot. The Moon Breathing Style has 16 forms, and it mainly used with Kokushibo's Blood Demon Art.
8. Flower Breathing. It's a Breathing Style derived from Water Breathing. The users are Kanae Kocho and Kanao Tsuyuri. The Flower Breathing Style has 7 forms.
9. Insect Breathing. It's a Breathing Style derived from Flower Breathing. The user is Shinobu Kocho, and she's the Insect Hashira and she's Kanae younger sister as well. The Insect Breathing Style has 4 forms.
10. Serpent Breathing. It's a Breathing Style derived from Water Breathing. The user is only Obanai Iguro, he's the Serpent Hashira too. The Serpent Breathing Style has 5 forms.
11. Love Breathing. It's a Breathing Style derived from Flame Breathing. The user is Mitsuri Kanroji, the Love Hashira. The Love Breathing Style has 6 forms.
12. Sound Breathing. It's a Breathing Style derived from Thunder Breathing. The user is only Tengen Uzui and he's a Sound Hashira. The Sound Breathing Style has 5 forms.
13. Mist Breathing. It's a Breathing Style derived from Wind Breathing. The user is Muichiro Tokito and he's a Mist Hashira. Mist Breathing Style has 6 standard forms and a seventh one created and utilized by the current Mist Hashira, Muichiro Tokito.
14. Beast Breathing. It's a Breathing Style that is distantly derived from Wind Breathing. The current user is only Inosuke Hashibira. The moves of Beast Breathing didn't called "Forms" but it called "Fangs" instead, so the Beast Breathing Style has 11 Fangs (Forms).
And that's all of the Breathing Styles of the Demon Slayers and see you next chapter!