TVP is quite an important part of the vegetarian diet in the Western meat-eating countries because it allows the vegetarian to use traditional Western food recipes and simply substitute a TVP product for meat. It is also often used as a meat substitute for non-vegetarians without telling them (like in some school cafeterias.
Textured vegetable protein is generally made from the soya and is essentially hard tofu made to look and taste like meat. The look is not hard to master, the taste depends on the manufacturer.
The TVP products made by Morningstar Farms seem to be the most successful: They make TVP hamburgers, patties, hot dogs, etc. In the US they can be found in your grocer's freezer.
Linda McCartney, the late wife of Paul McCartney, popularized TVP among English-speaking vegetarians on both sides of the Big Pond. In one of her books she said how surprised her guests were when she served them traditional Western dishes: "We thought you were vegetarians." The dishes she served were indeed vegetarian but her guests couldn't tell the difference, even though she told them they were made from TVP.
My personal favorite is TVP Stroganoff.