Difference between accessing SQL Server by instance name and cluster name

Question

I have installed failover clustering feature on two servers with Windows Server 2012 and then I installed SQL Server 2012 on both of them. I also enabled SQL Server 2012 AlwaysOn feature.

Now I can access each node by instance name. I can also connect using failover cluster name.

What is the difference between accessing SQL Server by instance name and cluster name?

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I have two nodes. I can connect to each node separately or by using cluster name. When I create a database with cluster name, database will be created on one node. I dont have shared storage and that is not the requirement of AlwaysOn.

Consider the scenario that you created a failover cluster using two nodes. you don't have a shared storage. You install SQL server on both nodes and you can connect to each node separately. You can also connect to cluster using cluster name. Is there any advantage in creating a database by connecting to the cluster? Does it failover automatically to another node when on node is down without using AlwaysOn?

I installed standalone instances and I read that clustered instances of SQL Server is not the requirement of AlwaysOn.