My first interaction with the world of Ivalice was with the Nintendo Game Boy Advance version of this game, Final Fantasy Tactics Advance and I was hooked for over a year trying to strategically tackle the battles, upgrade my characters and continue the overall story. I eventually forgot the story and gave up on trying to follow it due to having to restart the game to do so (this was before I knew about fan sites, Wikipedia, etc).
Final Fantasy Tactics was unique in the series as it was the first to step outside of the tried and true gameplay formula that had been in use for almost 10 titles at the time. FFT takes the series into the strategy realm, turn based strategy at that, something that was not wholly that popular, at least on consoles (sure on PC, it was a thriving contender against First Person Shooters). Final Fantasy VII did offer a short real time strategy level or two to handle so Square was obviously testing the waters, so to speak.
FFT battles are set on a square based map with characters occupying one square at a time. Bosses can occupy more than one square (usually on the side of the current map). Much like Vandal Hearts, another classic strategy title on PSOne, there are counter-attacks to worry about, health and weapon proficiency for the characters.
A word of warning before diving into Final Fantasy Tactics- if you are short on time you may not want to try and play. Some battles can take upwards of 10 minutes to complete while others can be completed in a few minutes. There is no way to know before you start a battle though.