Flame ionization detection (FID) is a method of detecting organic analytes in gas-phase chromatography experiments. A very hot flame is used to burn the analytes emerging from the chromatography instrument, which produces positively charged ions. These ions are then attracted to a negatively charged electrode, which detects them by generating an amount of current proportional to the number of positively charged carbon atoms reaching the electrode. FID can be particularly useful due to the fact that it detects organic analytes without any interference from a wide variety of other gases, which can be present in the sample or in the carrier gas used in the gas chromatograph. There are some downsides to FID, one of which is that the sample is destroyed as it is analyzed.