system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How Dry Cleaning Works?
gpt
Dry cleaning is not dry in the sense that it's not wet, it's just dry in the sense that it doesn't use water.  Dry cleaning is a process of cleaning clothes using a chemical solvent to dissolve dirt off clothes rather than water and detergent.  The process started with Romans using Ammonia to wash clothes, then later we switched to petroleum based solvents like Kerosene and now the chemical is Perchloroethylene.

The advantage over water and detergent is that your home washer agitates the clothes pretty roughly to basically shake the dirt off, assisted by the detergent which reduces friction.  Dry cleaning more gently tumbles clothes through the much more powerful chemical solvents until all the dirt comes off or dissolves.  Also the fabrics tend to react less with dry cleaning chemicals than water.  Dry cleaning systems are closed and sealed, and the chemicals used are filtered and recycled due to their harsh natures.