What you need to know about the Israeli settlements

A January 26, 2017, photo of new apartments under construction in the Israeli settlement of Har Homa.

(CNN)Four issues have dominated the Israeli-Palestinian conflict as the most difficult to solve and the most complex to handle: the status of Jerusalem, Palestinian refugees (and their right of return), borders, and settlements.

Recent announcements by the Israeli government of the expansion of West Bank settlements, made in the period since Donald Trump became US President, have put settlements back in the spotlight. The announcements come just weeks after the UN Security Council Resolution declared that settlements had "no legal validity."

What are settlements?

Settlements are Israeli cities, towns and villages in the West Bank and the Golan Heights. (We will deal with East Jerusalem a bit later.) They tend to be gated communities with armed guards at the entrances. Why are they settlements and not simply Israeli residential areas? Because Israel is widely considered to be an occupying force in the territories. It is land that Palestinians, along with the international community, view as territory for a future Palestinian state.
Israeli soldiers stand guard blocking an entrance to the Jewish settlers zone of Hebron's Tel Rumeida neighbourhood, on September 18, 2016.

Why are the West Bank and East Jerusalem considered occupied territory?

Israel began its occupation of the West Bank and East Jerusalem in 1967 during the Six-Day War. Seeing a military buildup in the surrounding Arab countries, Israel launched a preemptive strike against Egypt, after which Jordan, in turn, attacked Israel. Israel annexed East Jerusalem shortly thereafter, unifying the city under Israel's authority. But Israel has never annexed the West Bank, part of which remains under military law.
Decisions in the West Bank are carried out by the Israeli military, not the civilian government. The Israeli military makes decisions on land use, freedom of movement of Palestinians, home demolitions, and many other areas.
Before 1967, the West Bank and East Jerusalem were under Jordanian occupation. Jordan annexed the territory in 1950, but few countries recognized the annexation as legal. Jordan renounced its claim to this territory in 1988, recognizing the Palestinian Liberation Organization (PLO) as the representative of the Palestinian people.