From another question:

Full table scans, index range scans, fast full index scans, nested loops, merge join, hash joins etc. are merely access systems that must definitely be understood through the analyst

Can someone explain each one of these as well as provide where I'm able to perform some further reading through in it?

For additional around the joins, I would suggest reading through some articles from Jonathan Lewis:

For more information on reading through Execution Plans and interpretation the things they mean I would suggest it:

Troubleshooting Oracle Performance by Christian Antognini

To begin with I suggest the relevant section of Oracle Database Concepts.

If you would like more detail, you are able to make reference to the Performance Tuning Guide as Robert indicated.