From this file, we can see that the groupId we want is "log4j" and the artifactId is "log4j". We see lots of different version values to choose from; for now, we'll just use the latest version, (some maven- files may also specify which version is the current release version). Alongside the maven- file, we can see a directory corresponding to each version of the log4j library. Inside each of these, we'll find the actual jar file (. log4j-) as well as a pom file (this is the for the dependency, indicating any further dependencies it might have and other information) and another maven- file. There's also an md5 file corresponding to each of these, which contains an MD5 hash for these files. You can use this to authenticate the library or to figure out which version of a particular library you may be using already.