Fire
Fire is a chemical change in the atmosphere, and forms heat, light, smoke and flames, which happens due to the oxidation of a substance. It is a symbol of life, as well it has the capability to destroy in seconds. It can range anything from a small flame to a gigantic hellfire. It gives light and illuminates homes, as well as acts as a fuel for cooking and is a provider of warmth. It can also be used to turn things into instant waste, as fire consumes certain materials by it's entirety and turns them to ash. Without fire, humans would almost cease to exist. However, fire requires oxygen to burn, meaning it is dependent on the atmosphere for it's survival and materialization. For me, fire personifies hope, as I have described above, as well as destruction; the ability of flooding entire forests with hellfire and rampaging everything in it's path. One last thing I want to mention is that, when used in a certain way, fire can heal wounds; cauterization.
Fire in Narutoverse
Fire Release is one of the elemental releases used in the Narutoverse and in the RP that utilizes one Fire nature chakra inside their core. It is a very violent element that breaths and spreads its power and destruction. It, in short; is the usage of superheated chakra to create flames and heat focused attacks. Its commonly created through channeling chakra to the user's lungs and heating it upto extreme levels, and forming Fire natured chakra, and then exhaling the built chakra in various forms. Fire chakra is most commonly used in its fire-based form, but it can also take the shape of superheated ash or flammable gas. Its considered the least versatile element among the basic 5 elements as it excels in offensive capabilities, and lacks very heavily in supplementary usage and is okayish as a defense. It's a fast element although not as fast as Wind or lightning. The main property of fire, is that it possesses a great level of heat, capable of incinerations. As mentioned above, the user, when generating fire superheats their chakra giving them this ability and it's usually generated from the mouth (though can be released from other points of release, i.e. hands, legs and other parts of the body). However, this property of heat can be used in various other ways. For example, one could add fire chakra to their bladed weapons, allowing them to easily cut harder objects like metals with ease, as well cause blunt force damage, along with violent burning power, which can potentially cause 3rd degree burns. One can also use heat to affect their opponent without actually burning them or requiring contact with the fire. The concept of the heat stroke, the amount of heat generated can be used in ways to increase body temperatures beyond safe points and initiate fatigue or illness that hinders your opponent. The heat of the element makes it capable of reducing earthen structures to molten mud, and form molten earth, if used right. Also, waves generated by the heat can be used to alter the density and behavior of the air. On a molecular level, the molecules in fire move at a rapid pace, which allows them to generate the type of heat they do. When speaking on the molecular structure, the rapid pace of this plasma element makes it a great element to work in conjunction with Lightning release. For one both are able to keep up with each other and Fire also covers for Lightning's weakness of Wind. Wind>Lightning for it being a natural insulator however Fire>Wind due to the augmenting properties the wind has to feed fire with the oxygen in the air (though not the case when Wind and Fire oppose each other necessarily). Joining a fire technique right after a lightning technique helps fortify a much stronger technique. Fire Release is naturally stronger to Water Release, and can turn entire bodies of water into steam and scorching mist, within seconds. Last, but not the least, Fire is the most ferocious element due to its sheer raw power and is the hardest to tame, due to it's near uncontrollable nature.
Chakra
"Chakra" is basically life essence or life force which exists in human bodies and animals. Without it, a shinobi can die. It can be considered "blood" and soul for a ninja. It is the molding of physical energies and spiritual energies in the body. Physical energy is the energy given off by the body cells and can be increased with more stamina and practise. Spiritual energy is derived from the consciousness of the mind and can be increased through great concentration and meditation. It is the basis for all almost all the ninja skills like Ninjutsu, Genjutsu, except Taijutsu in some special cases. It flows through the chakra circulatory system, and in it, there are 361 points aka nodes in the body known as tenkutsu. The function of the tenketsu is to regulate and control the flow of chakra. If these weren't present, then chakra would flow through some specific organ, thus there wouldn't be a balance in the chakra flow. Every ninja in the narutoverse possesses a chakra pool. Shinobis with a very high chakra pool like Naruto can perform a lot of higher ranked techniques like Multiple Shadow Clone Technique, etc. without having the fear of getting their chakra depleted at once. Senju Clan members for eg, have very high chakra reserves and a high physical energy aka high "Yang" energy, thus their naturally strong bodies and on the other hand, the Uchiha clan members have a very high spiritual energy, i.e. high "Yin" energy, thus their proficiency in genjutsu and visual prowess. It is possible to have high chakra if you possess very strong willpower. If chakra runs out completely in a shinobi, then he dies as shown when Kakashi died due to his chakra completely running out against Deva Pein. It can be divided into several types like:
Elemental Chakra
Senjutsu chakra
Bijuu Chakra
Ninjutsu means "Ninja Arts" and is something that allows the shinobi to do something that a normal human can't do, like walking on water, manipulating elements, the usage of special as well as bladed weapons, stealth, transformation, etc. The effects of ninjutsu are real. Most of the time, it heavily relies on the usage of handseals as well as chakra. Regular ninjutsu doesn't incorporate the usage of elements for it, like stealth, a basic Rasengan, etc. Elemental Ninjutsu is an advanced form of ninjutsu, which incorporates the usage of basic 5 elements, as well as advanced combinations to create stronger jutsus which have the respective properties of the 5 elements. Elemental ninjutsu is stronger to regular ninjutsu, since regular ninjutsu only uses raw chakra, whereas, elemental ninjutsu uses both Shape Manipulation and Nature Transformation. The perfect Rp example would be that, a Wind natured or a Lightning natured Rasengan would have a greater destructive force than a standard Rasengan, obviously because the elemental Rasengan contains violently rotating chakra as well as the violently rotating chakra is given the property of the respective elements.
Handseals
Handseals are hand gestures, which primarily manipulate chakra and dictate the exact amount of chakra needed for the respective specific technique. Weaving of handseals makes chakra take different "patterns". Some techniques require a large number of handseals, which is related to the complexity of performing that technique and if not weaved properly, in order, or if the user loses focus in between, then the technique is either executed in a weaker state, or it is dispersed midway, depending on the specific technique. A good example is Water Dragon Bullet Technique. It was shown that the technique required a string of 44 handseals to perform, however the Second Hokage, Tobirama could perform it with a single handseal, due to his unparalled Water mastery. It is shown in the manga that with time, a shinobi after mastering the specific technique, requires one-literally no handseals to perform it, an example being Chidori, which required some handseals when Sasuke just learnt it. In our RP, the user can perform any 2 elemental releases of his choice, depending on the elements he has placed as specialties, with one-virtually no handseals/faster handseals. Usually, handseals are performed with both the hands, but Haku, Minato, etc have demonstrated the ability to perform it with only a single hand. The 12 basic handseals are Monkey, Ram, Dog, Horse, Dragon, Boar, Rat, Snake, Ox, Hare, Bird, Tiger.