General terms used in POM

groupId:
Generally groupId refers to domain id. For best practices company name is used as groupId. It identifies the project uniquely.

artifactId:
It is basically the name of the Jar without version.

version:
This tag is used to create a version of the project.

Local repository:
Maven local repository the place where Maven stores all the project related jars files or libraries or dependencies. By deault the folder name is ‘.m2‘.

Central repository:
Maven central repository is the default location ‘http://mvnrepository.com/‘ which is used for Maven to download all the project dependency libraries. If there is any library or jar file required in the project, Maven first look it in to the .m2 folderof Local Repository, if it does not find the required libarary then it looks in Central Repository and download the libabry in to the local repository.