Editing Identification friend or foe

{{Status|Canon}}
[[File:IFFtags.jpg|thumb|IFF tags identifying UNSC soldiers.]]

'''Identification friend or foe''', or '''IFF''', is a system used by the [[UNSC]] to tag friendly or hostile units for easy identification on a [[heads-up display]] or [[motion tracker]].<ref>'''[[wikipedia:Identification friend or foe|IFF at Wikipedia]]'''</ref><ref>'''Halo: Contact Harvest''', ''page 178''</ref> The equipment of a friendly unit generates a signal on a specific frequency, which is interpreted as a "friendly" signal by the receiver. If a signal is not generated, then unit is tagged as a hostile. Friendly units appear as yellow dots on the motion tracker, while the crosshairs of a HUD turn green when pointed at them. Hostile units show up as red on a motion tracker, and the HUD crosshairs turn red.

All UNSC personnel are implanted with a [[neural interface]] containing an IFF transponder.<ref>'''Halo: Mortal Dictata''', ''page 292''</ref> Weapons like the [[MLRS-2 Hydra]] use an integrated IFF interrogator in its targeting systems to prevent friendly units from being targeted by the guidance system.{{Ref/Game|HI|In-game Hydra weapon|Detail=[[:File:HINF HydraIFF.png|Decal details]]}} Additionally, most UNSC ships, ranging from civilian [[freighter]]s to [[UNSC Navy]] [[warships]], possess IFF transponders displaying their identity, allegiance, and classification.<ref>'''Halo: Contact Harvest''', ''page 176''</ref>

During the [[Fall of High Charity|fall of High Charity]], [[John-117]] managed to rescue several [[UNSC Marine]] [[Prisoner of war|prisoners of war]]. This was due to [[Cortana]] identifying their IFF transponders, which were still with the Marines.<ref>'''[[Halo 2]]''', campaign level ''[[Gravemind (level)|Gravemind]]''</ref>

Following the [[Human-Covenant War|fall]] of the Covenant, the [[Swords of Sanghelios]] and [[Jul 'Mdama]]'s [[Jul 'Mdama's Covenant faction|Covenant]] utilized "semi-feral" associated intelligences to operate {{Pattern|Upisa'weri|Shrike}} turrets. As these constructs had been long abandoned, they could not communicate with modern [[Sangheili]] and had to be carefully monitored and locked down prior to activation due to their inability to understand contemporary IFF systems and codeword usage.<ref>[https://www.halowaypoint.com/en-us/universe/weapons/shrike-turret '''Halo Waypoint''': ''Shrike Turret'']</ref>

==List of appearances==
*''[[Halo: Combat Evolved]]'' {{1st}}
*''[[Halo: The Flood]]''
*''[[Halo 2]]''
*''[[Halo: Landfall]]''
**''[[Halo: Combat]]''
*''[[Halo 3]]''
*''[[Halo: Contact Harvest]]''
*''[[Halo 3: ODST]]''
*''[[Halo: Reach]]''
*''[[Halo 4]]''
**''[[Spartan Ops]]''
*''[[Halo 5: Guardians]]''
*''[[Halo: Shadow of Intent]]''
*''[[Halo: Silent Storm]]''
*''[[Halo Infinite]]''

==Sources==
{{Ref/Sources}}

[[Category:Communications technology]]