The HoloNet was a large communications system used by the citizens of the Galactic Republic and its successor state, the Galactic Empire. The HoloNet News was broadcast on the HoloNet during the reign of both governments.
After the frequent attacks by a rebel cell led by former Imperial Berch Teller on shipments headed for the Death Star's construction site, the newly-promoted Grand Moff Wilhuff Tarkin restricted use of the HoloNet to the Empire only. This decision, together with other plans enacted by the governor, was speculated by some to mean that an Imperial takeover of the Outer Rim was imminent.
During the Empire's reign, the Rebels used a secret HoloNet channel to broadcast secret information about the Empire's weaknesses to other freedom fighters. The Empire used the HoloNet to broadcast Imperial propaganda.