Hamas started as an offshoot of the Muslim Brotherhood in 1987. Its name means Islamic Resistance Movement.
It is opposed to the existence of Israel on what it says is Palestinian land. It wants a state based on Islam in its place and across the occupied West Bank, East Jerusalem and Gaza.
It has, however, signalled its willingness to accept an interim Palestinian state in just the West Bank, East Jerusalem and Gaza, without renouncing its claim to all of historic Palestine.
Before the 7 October attacks, Hamas was estimated to have about 30,000 fighters, but Israel said in August 2024 that its forces had killed more than 17,000 of them. This could not be independently verified.
Hamas became the sole ruler in the Gaza Strip in 2007, after winning Palestinian elections and violently ousting rivals.
However, as a result of the war, the group's infrastructure and ability to operate openly have been all but destroyed.
[SRC] https://www.bbc.co.uk/news/articles/clyv7w3gdy2o