What are kalamata olives?

I'm trying to include Mediterranean food into my diet and most of the recipes I found include kalamata olives. What are they? Do they come in jarred, canned and fresh varieties? Which are better and which are cheaper?What are kalamata olives?
It is just an olive that comes from a particular area of Greece and you wil just have to see if you get them there.



Kalamata is a region in Greece, famous for its production of olives and olive oils. In particular the Kalamata olive is often known as the Greek olive, and is distinct in taste and appearance from most green and black olives. When Kalamata olives are not used for olive oil, which is a fairly common use, they are normally brined, packed in olive oil or pickled in wine vinaigrette.



Unlike most green and black olives, Kalamata olives are a deep, rich aubergine in color. When they are soaked in vinegar or brined, they may appear almost dark brown or black. On the tree, these purple almond-shaped fruits are hard to miss because of their beautiful color. They also tend to pack more meat than the average black variety.



Most Kalamata olives are split prior to being brined or pickled, which allows the flavor, particularly of vinaigrette, to soak into the interior of the olive. Yet before you begin eating, be aware that these olives are usually sold with their seeds in. If you plan to serve these, eat them yourself, or add them to recipes, be sure to remove the seed first



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