What is diffrent between Jena and Sesame. I thought that Jena is an open source framework for storage, inferencing and querying of RDF data. But I found that exist something like Sesame and it has almost the same feature.
You are right, the features are similar. There has been some work comparing the performance of these two.
You can google "Jena vs Sesame" to find out more information.
Note that there are quite some users out there who are using just the Java APIs provided in Jena (Sesame). For example, one can use
Jena APIs to talk to Oracle database through the Jena Adapter (Sesame Adapter).
Oracle supports both Jena APIs and Sesame APIs. Note that there are more optimizations implemented in the Jena Adapter than those in
the Sesame Adapter.