Tech Level reflects the degree by which the character is familiar with advanced (or primitive) technology as well as its inbred predisposition for using what the world has to offer. This ability does not have a major impact on game mechanics though it allows the game to become a little bit more interesting by showing from how far different places the characters can origin.
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To determine character's Social Class, roll d100 and compare the result with a following table:
Of course both of these abilities are optional - you don't have to use it if you don't feel it.