Who Were the Philistines in the Bible?

Throughout the story of Samson, we run into the Philistines. In Judges 14 alone, we read that Samson married a Philistine woman, lost an unfortunate wager to 30 Philistine wedding guests, and killed another 30 Philistines from Ashkelon to pay his gambling debt. Just who were the Philistines? That question…