Electrons are subatomic particles that are found in atoms. They are negatively charged and have a much smaller mass than protons and neutrons, which are the other two types of subatomic particles.Electrons are found in the electron cloud, also known as the electron shell or electron orbital, which surrounds the nucleus of an atom. The electron cloud is divided into different energy levels, known as electron shells, and each shell can contain a certain number of electrons. The innermost shell, known as the K-shell, can hold a maximum of 2 electrons, the second shell, L-shell can hold a maximum of 8 electrons, and so on.The number of electrons in an atom's outermost shell, known as the valence shell, determines the chemical properties of the atom. Atoms with full valence shells are stable and do not tend to react with other atoms, while atoms with incomplete valence shells are more reactive and tend to form chemical bonds with other atoms.Electrons are also found in other forms of matter, such as ions, which are atoms that have gained or lost electrons, and in molecules, which are formed by the chemical bonding of atoms. Electrons are also found in conductors, such as metals, where they are free to move and conduct electricity, and in insulators, such as rubber, where they are not free to move and do not conduct electricity.In conclusion, Electrons are subatomic particles that are found in atoms. They are negatively charged and have a much smaller mass than protons and neutrons, which are the other two types of subatomic particles. They are found in the electron cloud, which surrounds the nucleus of an atom. The number of electrons in an atom's outermost shell, known as the valence shell.