What is the Difference Between a Sweater and a Cardigan?

I've been working on our sweater listings and in my research I came across an interesting question. What is the difference between a Sweater and a Cardigan? 

Sweaters are a knitted garment and can be either a cardigan or a pullover sweater. The key difference is that a Cardigan is a sweater that opens in the front. It can button, zip, or snap closed. A Pullover Sweater is the garment that you pull over your head - it does not have an opening in the front. 

Sweaters or Cardigans can be worn alone or layered over a tshirt or blouse. You can vary the look by changing the shirt style and color under the sweater. One thing I like about Cardigans is that they sometimes have pockets - something you rarely see on a Pullover Sweater. However, Pullovers can have a variety of necklines from V Necks to Turtlenecks so you get different looks. Pullovers are perfect for showing off a necklace or pendant. 

Interesting side note: "Why do they call it a cardigan?" The cardigan was named after James Brudenell, 7th Earl of Cardigan, a British Army major general. They say the cardigan is inspired by the knitted wool waistcoat that British officers wore during the war.