Diyarbakir is a very big area of land where people live and work. It's kind of like a really big neighborhood, but it's so big that it's its own special place where people get to decide who they want to represent them in the government.
The people who live in Diyarbakir get to vote for someone who will speak for them and make decisions for them. This is called electing a representative.
So, Diyarbakir is broken down into smaller parts called electoral districts. Each district has a bunch of people who live there and they get to vote for someone who they think will represent them best.
Think of it like picking a captain for your team! You want someone who will speak up for you and make sure that your team is doing the best it can. The people in Diyarbakir each get to pick their own captain to represent them and make decisions on their behalf.