Digital Analytics are the methods by which the information about your customers is gathered and analyzed. It is important to have the tools, the processes and the people in place to support the measurement, reporting, analyzing, testing and improving of your business practices.
There is a very famous quote "There are three kinds of lies: lies, damned lies, and statistics." often attributed to Benjamin_Disraeli (1804–1881)
What are segmentation and context and why do they matter to your business?
Aggregated data gives you the overall trend of the data, so for example are your sales going up or down or are they flat. Segregation of the data tells you what are the factors driving your sales, and context tells you how you are doing in relation to the rest of the people in your same type of business and how you are doing now vs how you were doing.
Conversions track the customers progress in your website and attributions are what those conversions can be attributed to. This can be a complex or a relatively easy to understand analysis.
The measurement system must be designed to for your business and what you hope to accomplish. For example here are 5 types of sites and what they might want to be measuring as their Macro Conversion.