This review discusses the application of the aerogel as radiator in Cherenkov detectors. The talk gives the view on the history of use of aerogel in detectors for particle physics experiments. Physical principles of such detectors construction and operation are described. Data on threshold Cherenkov counters with direct light collection and on those using wavelength shifters are presented. Also presented are data on Ring Image Cherenkov detectors with single and multilayer focusing aerogel radiators.