Okay kiddo, have you ever heard of a column? It's a tall, thin thing that holds up other things like buildings or bridges. Now imagine if there was a special kind of column that was made to honor important people or events in the past. That's what the Marian and Holy Trinity columns are!
The Marian column is a type of column that was usually built in European towns and cities to honor Mary the mother of Jesus, who is very important in the Catholic Church. These columns usually have a statue of Mary at the top, and sometimes there are other statues or carvings lower down on the column. People would gather around these columns to pray and show their respect for Mary.
The Holy Trinity column is another type of column that was built in Europe to honor the Christian belief in the Holy Trinity, which is the Father, Son (Jesus), and Holy Spirit. These columns usually have statues or carvings of these three figures, and sometimes there are other religious figures or symbols on the column too. People would gather around these columns to pray and show their respect for God.
Both of these types of columns were built a long time ago, when religion was a very important part of people's lives. Nowadays, some people might still appreciate these columns for their historical or artistic value, but not as many people gather around them to pray anymore.