Okay, so you know how when you go to school, your teacher reads things to you and asks you questions about what they said? Well, in some churches, there are people called lectors who do a similar thing.
During a church service, the lector stands up in front of everyone and reads from a special book called the Bible. The Bible has a lot of really important stories and teachings that people need to hear, and the lector is responsible for making sure everyone in the church can hear them.
Sometimes the lector also helps the priest by giving out special papers or guiding people to certain parts of the church. It's a very important job, because without the lector, people might not be able to hear the important messages that the Bible has to offer.
So, in short, a lector is like a teacher in church who reads important stories and teachings from the Bible to help everyone learn and understand them better.