simply, IQOPTION is a trading platform. You can trade cryptocurrencies such as Bitcoin, Ethereum, Ripple, you can trade fiat currencies such as Dollar, Euro, Yen or you can trade company shares such as Facebook, Google, Uber etc. There are few ways to trade in IQOPTION. The most famous is Binary Option, forex also available for those who knows how to trade in longer time frames.
in simple words, Trading means buying a share or currency and then selling it for a gain or vice versa. For an example you can buy a facebook market share at $200 and sell it for $220 when it goes up in price. you can learn more about trading from this article.
A binary option is where the buyer receives a gain for a successfull trade for their investment. Binary means two. This two options in Binary trading is 'going up' or 'going down' of the price of the currency or the share. If your prediction is correct within the expiry time of the given trade, that means you have executed a successfull binary trade. You can learn more about binary trading from this article.
You can register from the following link and start trading using your $10,000 DEMO account to test out the platform.