A common source of confusion is the nature of the obligations related to selling an option, like a vanilla call or put. If we sell a call option, are we obligated to sell the underlying asset to the holder if the option is exercised? The source of confusion is the kind of market on which the option is sold. The writer is the one selling the option first on primary markets. Then the option, assuming it is an exchange-traded one, may change hands on secondary markets, but the obligation is only assumed by the original writer. If we buy and then sell an option, we are just selling the rights to a new holder, incurring a profit or a loss. To avoid any ambiguity, we shall always use the term "option writing" when we mean "selling on primary markets," collecting the option premium and assuming the obligations stated in the contract. When we talk about "selling" an option, it will always refer to secondary markets, as part of a trading strategy.