Why do the particles attract each other?

Hint: A particle (or corpuscule in earlier literature) is a small localized entity to which many physical or chemical attributes, such as volume, density, or mass, can be assigned. From subatomic particles like the electron to tiny particles like atoms and molecules to macroscopic particles like powders and other granular materials, they vary significantly in size and number. Particles can also be utilized to build scientific models of even larger things, such as individuals moving in a crowd or heavenly bodies in motion, depending on their density.

Complete answer:
The forces of attraction and repulsion that act between adjacent particles are known as intermolecular forces (atoms, molecules, or ions). In comparison to intramolecular forces like covalent or ionic bonds between atoms in a molecule, these forces are weak.
Intermolecular Attractive Forces of Different Types
Hydrogen bonding is an example of dipole-dipole forces, which are electrostatic interactions between permanent dipoles in molecules.
Ion-dipole forces are electrostatic interactions between one molecule's partly charged dipole and a fully charged ion.
Instantaneous dipole-induced dipole forces, also known as London dispersion forces, are the weakest of intermolecular interactions and are classified as van der Waals forces. They are generated by correlated electron motions in interacting molecules.
Particles of matter are drawn to one another by an intermolecular force known as the intermolecular force of attraction. The intermolecular force of attraction varies across the three states of matter.
Solids have the maximum concentration, which explains why they are strong and do not change their structure.
It is much less in gases since gases are not rigid and may adopt the shape of a vessel and be squeezed.
Liquids have a force of attraction that is weaker than solids but stronger than gases. Liquids are not solids and are not as compressible as gases.

Note:
The force of attraction is a force that attracts the body closer together. In nature, there are various attractive forces at work. Magnetic force, electric force, electrostatic force, and gravitational force are some of them. The gravitational pull is a well-known example of attraction since it attracts things to itself regardless of their distance. The universal law of gravity, developed by Newton, explains a lot more about how this force works. Every mass in the cosmos draws some other mass in the universe, according to this theory. It proves that anybody who throws up will come down.