Each Oracle release has many differences.
All the changes you can read here. These are Developer related. We can refer at one place.
There are architectural differences.
Related articles
- Another 5 neat 12c features for Oracle developers (iadvise.eu)

How to Build and Deploy Code in AWS, You need These 4 Services
Organizations need speed deployment at scale. AWS provides a service called code pipeline, which is a four-step process explained here.

How to change Date Format in SQL? These are Helpful Functions
Date conversion in SQL simplifies your work, and you will get the desired result. These two functions most people use in the production code.

Hadoop Adaptive MapReduce Points to Read now
The performance and the approach of Adaptive MapReduce in Hadoop explained.