blackjack index

Recently, I have taken an interest in building a blackjack simulator for personal use/analysis. Long term is to get it to compute accurate indices for both a single parameter system and any accompanying side count parameters (multi-parametric analysis.) For a while, it seemed like it was to be...

I'm sorry I just want to get the terminology down but is a blackjack index just basic strategy and the changes when there are rule changes in the game? I know that basic strategy changes slightly depending on the number of decks, weather surrendering is available, etc. I just want to make sure...