We all know what is cryptocurrency,I feel like I don't need to say what is it,but for someone who isn't familiar with it. It's a digital currency that is encrypted with a system called "blockchain",and this system is near to being not hackable.
The cryptocurrency's market is so alike to that of the stock's market,Like Bitcoin for example maybe today for 1000$ and tomorrow for 900 or 1100. It depends on your understanding to the market,and you need also to know everything about the coin that you're gonna invest in,or mine. If you dont have much expertise in cryptocurrency I suggest that you should mine it rather than buying it. and if you want my advice,I suggest that you read carefully about the coin you'll invest either time or money in,and also to know the specifications of your device and how much hash/s it makes,you'll find plenty of calculators for this. Make Money with Cryptocurrency
Hope that this was helpful,and sorry that I couldn't help you much,but I'd rather send you to who can help you,because all what we care about here is your own benefit.