France (mostly Burgundy)
From Chardonnay's home base, these are the wines that inspired the rest of the world. In general, these tend to be dry, crisp, and firm when young with apple and pear flavors and sometimes a pronounced minerality. Although rarely overtly oaky, they can offer mild wood spice and toasted bread notes. Unlike most other examples, these age well, becoming softer, richer, and much more complex after a few years in bottle.
Americas (mostly California)
California took Chardonnay to new levels of richness and for many years the preferred style was full-bodied, luscious, buttery, and oaky. Recently there has been movement toward a more balanced approach with less toasty oak and fresher, more vibrant fruit flavors. That said, California Chardonnay usually equates with a rich buttery oaky style.
Australia, New Zealand
There is quite a range here, from elegantly produced citrusy versions that are slightly richer than Burgundy to tropical fruit bombs that are bursting with pineapple, lemon, white peach, and butterscotch.
Other regions of the world that produce Chardonnay often mimic one of the above-mentioned styles. As a general rule of thumb, European examples will offer less ripe fruit and oak notes while New World regions (from Chile to Australia) produce softer wines with more obvious ripe fruit and oak.