Ivy - Repository 'co-ordinates'

If Ivy just told the repository server give me john.jar, the repository server will ask, "The one from John Lennon or John McEnroe? And you want version 1.0 or 2.6.2?"

This is called co-ordinates.

Each company/organization/individual that uploads jars to the repository is assigned a unique 'address space'. For example, log4j has 'log4j' (what a surprise), apache has 'org.apache', hibernate has 'org.hibernate', etc

Each company can then create its own address space inside for its different jars.
For example, Spring has the address space org.springframework, under which it has spring-aop, spring-core, spring-jmx, spring-jca, etc

So if Ivy wants the version 2.3 of spring-jmx.jar, it will tell the repository server:
organization = org.springframework
jar name = spring-jmx
revision = 2.3

These 3 specifications are called the co-ordinates of the jar.