Annibale Bugnini was an important person who helped change the way that the Catholic Church celebrated its special events, like holy days and weddings. He was like a chef who wanted to update a recipe that had been used for a long, long time.
Before Bugnini, the Church used a special book called the Missal that had instructions for how to celebrate these important events. But some people thought that the way the Church did things was too old-fashioned and needed to be updated so that it could be more understandable for modern times.
So, Bugnini and his friends worked together to make some changes to the Missal. They made it more like a cookbook, with step-by-step instructions for how to celebrate holy days and weddings. They also changed some of the words to be more modern and easier to understand.
But not everyone liked these changes. Some people thought that the old way was better, and they said that Bugnini and his friends were trying to change too much too fast. So, there was a big debate, and some people even got very upset.
In the end, though, Bugnini's changes were approved by the pope, and they became the way that the Church celebrated its special events. Some people still don't like the changes, but many others think that they are a good thing and have helped make the Church more accessible to everyone.