There are many metadata management tools and solutions. Some specialize in data discovery, search, lineage, others in business processes. If you want to start small and learn as you go, give open-source tools a chance.
Data models describe how a user interacts with the data. It is an abstraction layer, or to be more precise - a set of layers. In simpler words, it's a plan or outline for an end-user how to understand data.
In the article I explain 4 models: storage, physical, logical and domain model.
Metadata is simply data about data. It is a description and context. In my opinion, metadata is as important as the actual contents. How can you possibly trust the contents if you don't know who collected it, how and why?
Data governance is a combination of physical systems, data models and business processes. Learn the core concepts by exploring available libraries and tools.
The cloud computing is the future. Cloud services slash the development time, enable novel possibilities. And at the same time, expose to new risks. Do not rely blindly on a cloud provider or the security department. Understand security threats and be able to mitigate them.