Cleaning removes visible dirt, dust and grime from a surface using soap or detergent and water. It makes a surface look clean and removes a portion of germs along with the physical mess, but it doesn't specifically target or kill remaining bacteria and viruses.
Sanitising reduces germs on a surface to a level considered safe by public health standards, typically through a chemical agent applied after cleaning. It's a step up from cleaning but doesn't necessarily eliminate all pathogens present.
Disinfecting goes further again, using stronger chemical agents to kill the vast majority of bacteria and viruses on a surface. It's the appropriate standard for high-risk areas or after illness, but isn't necessary for every surface in every setting, understanding which level a space actually needs avoids both under- and over-treating it.
