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A useful five-part classification is electrostatic double-layer, dispersion, steric, depletion force and solvent-mediated interactions. It is a practical classification rather than a unique exhaustive list.

Electrostatic double-layer forces arise from surface charge and mobile-ion redistribution. Like-charged surfaces often repel; opposite charges can attract. Their range changes with salt screening. London dispersion forces comes from correlated electronic fluctuations and is one contribution to Van der Waals force; its sign and strength across a medium depend on dielectric response.

steric stabilization occurs when adsorbed or grafted layers overlap, increasing chain confinement and/or local osmotic free energy. depletion force arises when smaller nonadsorbing solutes are excluded from a narrow gap: their greater accessible volume outside favors bringing the large particles together. Structured-solvent forces include short-range hydration force and hydrophobic attraction; their microscopic origin differs from the depletion force of an added solute.

The original sketches show double-layer overlap, a polymer-coated gap, depletion force exclusion and solvent structure, alongside a dispersion-potential curve. A realistic suspension can experience several simultaneously. Charge neutrality of a particle does not remove dispersion, steric or solvent-mediated interactions.