Trades in Futures & Options were mainly intended to be a hedging tool to help investors nullify their losses in other assets.
I.e. In case you invested in the stocks of a company and expected it to rise, you could hedge your risks by opting for an F&O contact taking a contrary position. This way even if one of your estimates went wrong the other would help you recover your losses.
However, presently F&O contracts are also used for speculation (buying just an F&O contract expecting the price to rise or fall) and reaping profits in case the expected price is achieved. Being market linked contracts/ instruments, Futures & Options are exposed to the shifts caused in the market prices of their underlying assets. They should be invested in after analysing the general direction of the market & the asset. Among Futures & Options, the latter may be considered as the more secure instrument as they provide more clarity on the possible loss one may incur and also can be invested in for lower amounts.