If you are a particle physics enthusiast, then you very well remember the year 2012. It was the time when CERN scientists confirmed the detection of the long-sought Higgs boson, also known by its nickname the "God Particle", at the Large Hadron Collider (LHC). But, what's the big deal about this Higgs Boson and the LHC, and what is it anyway? Well, it all begins with the Standard Model and elementary particles. The elementary particles are the smallest known building block of atoms, which have no internal structure and are considered zero-dimensional points that take up no space, and the Standard Model of particle physics is a theory that explains how the basic building blocks of the universe i.e. matter interacts, are governed by the three fundamental forces - electromagnetic, weak, and strong - and defines all these known elementary particles like quarks, leptons, bosons, etc. However, there were two problems with the standard model as it predicted, with the basis of quantum field theory and the Dirac equation, that all elementary particles shouldn't have mass, meaning they all should be traveling at the speed of light similar to a photon, and there should exist another particle describing the fourth fundamental force i.e. gravity as a graviton. However, we so far have found no evidence of a graviton and if all elementary particles are supposed to be massless, then why were we able to figure out the mass of an electron, which is around 9.10938356 × 10-31 kilograms. To solve one of these problems, we introduced the Higgs field.
In scientific terms, the Higgs field is a field of positive potential energy that is thought to exist in every region of the universe that continuously interacts with other particles, such as an electron, to slow it down, leading to it gaining mass. So, essentially the interactions that elementary particles have with the Higgs fields result in the mass of these particles. Simplifying that, the Higgs field, just like how all elementary particles have their own fields as previously discussed in the "Understanding Quantum Field Theory" article, has its field, but instead of it being at zero, it is filled with positive potential energy. So, whenever specific elementary particles like electrons pass through the Higgs fields, the fields slow the particle from traveling at the speed of light, which essentially means it's harder for it to travel aka heavier, gaining mass. If you are still confused try this. Assume you and your friend are racing, but you represent an electron and your friend represents a photon. The universe now is unfair, and because you are an electron, you will be faced with a swimming pool to run through while your friend (photon) will be going through the land. The path that you are taking to run is essentially the Higgs field and depending on your particle type, the fields react differently. Now, let's dig a little deeper into what interactions are taking place with the electron (sciency stuff). All elementary particles have an intrinsic quantum property called spin aka Chirality, which can be described as left and right-handedness (rotation direction), and particles seem to evolve into different handedness, depending on their circumstances. For example, the electron changes its chirality or handedness depending on the presence of weak hypercharge, which we can consider as particle x, where a photon doesn't seem to be changing its chirality even in the presence of this article x. As you can guess, this weak hypercharge is provided to the electron by the Higgs field that leads it to change its chirality that directly correlates with the particle's slowed down speed, which in turn gives the particle its mass.
Hoping that you understand what the Higgs field is, let's deal with what the Higgs boson and the LHC are? Starting with the simpler one, the LHC aka the Large Hadron Collider is the world's largest particle accelerator. It can accelerate particles at nearly the speed of light and collides similarly accelerated particles with each other in order to analyze their debris during the collision. Essentially, by breaking/smashing open protons and neutrons, scientists figured out the existence of subatomic particles like quarks, leptons, etc. Similarly, in 2012, scientists discovered a new particle called the Higgs Boson, and as the name suggests, it proved that the Higgs field indeed exists and made the human race, one step closer to creating the theory of everything. Let's not get too ahead of ourselves but how does a particle prove the existence of a field? So according to the quantum field theory, it states that all elementary particles are just fields or have fields that cover up the entire universe. The particle is just evidence of excitation or a peak in the field. Working backward, if scientists were able to find a Higgs boson aka a particle, then that would also suggest that there must exist a Higgs field of the particle i.e. an excitation or peak in the field. In the end, physicists were able to figure out why particles had mass and again were one step closer to creating the theory of everything. I personally also feel that further research on the Higgs field might explain Dark Energy and Dark Matter because Dark Energy seems to be existing everywhere in the universe and the Higgs field is the only other thing that exists everywhere else in the universe that too with a positive energy state