Call writers and put writers (sellers), however, are obligated to buy or sell if the option expires in-the-money (more on that below). This means that a seller may be required to make good on a promise to buy or sell. It also implies that option sellers have exposure to more, and in some cases, unlimited, risks. This means writers can lose much more than the price of the options premium.
The contract specifications are specified for one contract, so the tick value shown above is the tick value per contract. If a trade is made with more than one contract, then the tick value is increased accordingly. For example, a trade made on the ZG options market with three contracts would have an equivalent tick value of 3 X $10 = $30, which would mean that for every 0.1 change in price, the trade's profit or loss would change by $30.
The price at which you agree to buy the underlying security via the option is called the "strike price," and the fee you pay for buying that option contract is called the "premium." When determining the strike price, you are betting that the asset (typically a stock) will go up or down in price. The price you are paying for that bet is the premium, which is a percentage of the value of that asset.