To understand and appreciate wine, being able to note the different characteristics of each grape is important, in terms of being able to judge each grape’s uniqueness. 

All red grape-based wines are not created equal, same goes for whites.  Merlot, Pinot Noir and Cabernet Sauvignon may all look similar in the glass but each has its own distinctive attributes.  Grapes of the same variety, grown in different vineyards and vinified differently will always exhibit certain qualities which are ingrained in the grape’s unique nature.

For one to recognize what a grape’s evolution should be, from the vine to the glass, in key.  Building on that, to be aware of what a grape at it’s fullest potential may reach is the core of fine wine appreciation.

Here is a video with some examples of wine characteristics.

Source: examiner.com