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Maven parent
Under the parent tag, we can see a reference to a parent Maven project. This project contains references to the different sprint components, and third-party libraries as well, through a Bill Of Materials (BOM) file.
A BOM file indicates the versions that have been certified for a particular project but does not include them. This is a way to indicate what known versions this project works with. We will include the dependencies required as part of the POM project and it will use the versions provided by the BOM by default, so we can omit which versions to choose, however, we could specify different versions if we like to.
When we are more familiar with the different projects that we like to make and the dependencies versions that we need, it is a good idea to create our own parent project that has exactly what we require.