A resistance movement is a group of individuals who are resolved to fighting off an occupying enemy force, usually by guerrilla warfare.
The French Resistance movement was formed after the occupation of France by German forces during World War II. They used secret messages, sent by courier, to co-ordinate attacks on German targets with British and American forces. (VOY: "The Killing Game", "The Killing Game, Part II")
The Maquis resistance movement was formed in 2370 by the residents of several disputed planets in the United Federation of Planets-Cardassian Union demilitarized Zone, after the Federation decided to turn control of the area over to Cardassian forces. (DS9: "The Maquis, Part I", "The Maquis, Part II", VOY: "Caretaker" et al)
In 2375, Legate Damar formed the Cardassian Liberation Front, a resistance movement against the oppresion of Dominion forces in Cardassian space. The majority of the resistance was made up of former Cardassian military officers and, as such, had little or no training in guerilla tactics. The newly appointed Commander Kira was sent by Starfleet to provide assistance in this matter due to her experience during the Cardassian occupation of Bajor years earlier. (DS9: "Strange Bedfellows", "The Changing Face of Evil", "When It Rains...", "Tacking Into the Wind")
Unimatrix Zero was a virtual environment turned resistance movement created in 2377 by Borg drones who had regained their sense of individuality. Though the virtual environment was eventually discovered and destroyed by the Borg Queen, several drones had managed to gain control of the vessels they were on and continued their resistance against the Borg. (VOY: "Unimatrix Zero", "Unimatrix Zero, Part II")