These are actually 2 of many Spring Framework modules. You can easily find what packages these artifacts contain, using this site:
http://mvnrepository.com/artifact/org.springframework/spring-core/3.1.1.RELEASE
This can give you information about classes contained within a particular artifact and probably about the its purpose.
For Spring Framework, spring-core contains mainly core utilities and common stuff (like enums) and because it’s really critical for Spring, probably all other Spring modules depend on it (directly or transitively).
In turn spring-context provides Application Context, that is Spring’s Dependency Injection Container and it is probably always defined in POMs of artifacts that use Spring Framework somehow. In fact, spring-context depends on spring-core so by defining spring-context as your dependency, you have spring-core in your classpath as well.