Post-foundationalism

Can someone explain to me the essentials of post-foundationalism? Does it mean that there exist no central, knowable, basic foundational beliefs (like, for example, that the chair I’m sitting in really exists), or does it mean that the project of building up an entire worldview through rational constructs from those foundational beliefs is not valid?

I need some guidance on this one, because the stuff that’s being written about it seems to be unclear even in it’s own self-concept. First person to explain it well gets to name my daughter.

(all namings must be approved by Gretchen, and will likely be rejected outright, since she’s pretty much settled on the perfect name already)