Halfwine.com

A screw cap is a metal cap that screws onto threads on the neck of a bottle, generally with a metal skirt down the neck to resemble the foil of a traditional wine capsule.

Compared to cork, screw caps reduce the wine faults of oxidation and of cork taint. Screw caps are also generally perceived as easier to open. Screw caps have a much lower failure rate than cork, and in theory will allow a wine to reach the customer in perfect condition. We have experienced screw cap wines to be off - see here for more.

However, cork has a centuries-old tradition behind it, and there are also concerns about the impact of screw caps on the aging of those few wines that require decades to be at their best. A relatively large number of winemakers have been using screw caps for 20 or so years now and no negative reports about aging have arisen. If you want to get deeper into alternative wine closures to cork, the Winefolly blog has quite a detailed review – see here