Shia Islam is a type of Islam where people believe that their leaders are chosen by God, and they are called Imams. They think that these Imams are chosen by God to guide and teach people about Islam.
Shia Muslims believe that the first Imam was Ali, who was the cousin and son-in-law of the Prophet Muhammad. They think that Ali should have been the leader right after Muhammad died, but instead, other people took over. Shia Muslims think that the other leaders that came after Ali were not chosen by God, so they don't recognize them as leaders.
Shia Muslims believe that there are 12 Imams in total, and they think that the 12th Imam, Imam Mahdi, is still alive but hidden. They believe that when the time is right, he will come back and help make the world a better place.
Shia Muslims also have some different practices and beliefs than other Muslims. For example, they practice different ways of praying and fasting, and they have different beliefs about certain historical events in Islam.
Overall, Shia Islam is just one of the many different types of Islam that people practice all around the world.