Flow cytometry is the science of measure the physical and biochemical processes on cells and cell-like particles. This analysis is performed in an instrument called the flow cytometer. FACS Analysis is the short-hand expression for this type of cell analysis
The term FACS stands for Fluorescent Activated Cell Sorting, a term first coined by Len Herzenberg in the 1970’s, and later trademarked by Becton Dickinson. Since that time, FACS has come to be used as a generic term for all of flow cytometry, even though it is a specific trademarked term.