When buying or selling options, the investor or trader has the right to exercise that option at any point up until the expiration date - so simply buying or selling an option doesn't mean you actually have to exercise it at the buy/sell point. Because of this system, options are considered derivative securities - which means their price is derived from something else (in this case, from the value of assets like the market, securities or other underlying instruments). For this reason, options are often considered less risky than stocks (if used correctly). 
Just like many successful investors, options traders have a clear understanding of their financial goals and desired position in the market. The way you approach and think about money, in general, will have a direct impact on how you trade options. The best thing you can do before you fund your account and start trading is to clearly define your investing goals.
To reiterate, buying options in times of low volatility could prove to be advantageous should the volatility increase sharply. On the other hand, a lack of deviation in the price of the underlying asset will produce lower market volatility and even cheaper option premiums. Once again, pricing is relative and dynamic; "cheap" doesn't mean that it can't get "cheaper".
When buying a call option, the strike price of an option for a stock, for example, will be determined based on the current price of that stock. For example, if a share of a given stock (like Amazon (AMZN) ) is $1,748, any strike price (price of the call option) that is above that share price is considered to be "out of the money." Conversely, if the strike price is under the current share price of the stock, it's considered "in the money." 
A sampling of terms defined includes: active premium, aggregation, angel financing, asset allocation, backwardation, benchmark, bridge loan, capital structure arbitrage, coefficient of determination, commodity option, convertible arbitrage, deferred futures, discretionary trading, distressed debt, enumerated agricultural commodities, extrinsic value, follow-on funding, hedge ratio, interdelivery spread, long short equity, modified value-at-risk, offshore fund, piggyback registration, social entrepreneurship, systematic trading, tracking error, underlying futures contract, venture capital method, and weather premium.
For instance, it is possible to construct an option strategy in the futures markets that is affordable without sacrificing the odds of success...but with the convenience comes theoretically unlimited risk. This is easier than it sounds, similar to the way you would borrow money to pay for a house or a car, you can borrow money from the exchange to pay for long commodity option trades. There are an unlimited number of combinations of self-financed trades but they are typically going to involve more short options than long options, or at least as much premium collected on the sold options than that paid for the longs. In essence, the money brought in through the sale of the short options goes to pay for the futures options that are purchased. The result is a relatively close-to-the-money option with little out of pocket expense but theoretically unlimited risk beyond the strike price of the naked short options.
So, call options are also much like insurance - you are paying for a contract that expires at a set time but allows you to purchase a security (like a stock) at a predetermined price (which won't go up even if the price of the stock on the market does). However, you will have to renew your option (typically on a weekly, monthly or quarterly basis). For this reason, options are always experiencing what's called time decay - meaning their value decays over time.