An option giving the buyer the right to purchase an underlying security at a fixed price (strike price) and within a specific period of time (expiry date).
Call: An Option contract that gives the holder the right to buy the underlying security at a specified price for a certain, fixed period of time.
Option: A contract that gives the owner the right, but not the obligation, to buy or sell a particular asset (the underlying stock) at a fixed price (the strike price) for a specific period of time (until expiration) . The contract also obligates the writer to meet the terms of delivery if the contract right is exercised by the owner.
Covered Call Option Writing: A strategy in which one sells call options while simultaneously owning an equivalent position in the underlying security or strategy in which one sells put options and simultaneously is short an equivalent position in the underlying security.
Uncovered call option writing: A short call option position in which the writer does not own an equivalent position in the underlying security represented by his option contracts.