The electron is extremely small compared to all the other parts of the atom. It is negatively charged. The negative charge balances out the positive charge of the protons in the atom. Electrons are found in the electron cloud that surrounds the nucleus of an atom. The clouds are generally organized into shells. Electrons move at a quick pace, so you never really know where they are specifically. But after years of doing experiments, scientists discovered specific places where they can be found. The shape of the shells change depending on how many electrons the element has. The shell shape will be more complex if you have more electrons in that element. Electrons play a huge role in chemical bonds. An electron being transferred from one atom to another is called electrovalent bonding, which is also known as ionic bonding. Another type of bonding is called covalent bonding, which is where electrons are equally shared between two or more atoms in a cloud.
John Joseph Thomson, also known as J.J Thomson, discovered the electron in 1897. He was a physics professor at Cambridge University in the UK. He places cathode tubes in electric and magnetic fields. In the experiments he did, the cathode rays bent over to one side. Thomson knew the cathode rays must be made of some particle which he a dubbed a “corpuscle.” He initially thought his corpuscles were too small to be of interest to anyone outside the science lab. But, people quickly realized that electric current was made of moving electrons. Since a lot of things are made out of electricity, the electron turned out to be interesting to just about everybody.
In conclusion, the discovery of an electron has made, I guess you would say, a huge impact in science. Now they know more about electrons and how they work and how in an element, you have the same number of electrons and protons to equal out the positive and negative balance.