To be “long” means to own a security, and to essentially be bullish on it. A long position is to own a security and to expect it to appreciate. When people buy stocks, they are “long” those stocks.

Listening to fund managers giving market commentary, you may hear them say they are “long” on China or Industrials or Apple Inc., and this means that even though they may have hedged their position with some “short” sales, their outlook for those markets is optimistic and their bullish bets outweigh their bearish ones.

“Shorting” is the opposite of long positions, and it means to sell an equity or option that you expect to depreciate. Shorting can work in concert with long positions to mitigate risk exposure.