Bitcoin is the prime choice for long-term investment. Altcoins are the way to make profits in the short term. Altcoins are more risky than Bitcoin. Learn more about the project itself before investing in the altcoins you see. Don't be fooled by "surfaces". Many altcoin projects are scams. Don't trust strangers easily. No one wants others to be luckier and richer than themselves.
It is very important to not be fooled by the image that the scammers are trying to sell, scammers are very good at emulating good projects as not only they steal their image but they even steal their white paper and just change a few things here and there so their project looks to be a legitimate one.
However if you really do your due diligence you will see a few cracks on their facade, and you must never ignore them as those cracks should be enough of a read flag for you to ignore that project, however we need to also be honest and say there are some scams that are incredibly obvious, like those which offer a huge return on your investment, and yet those projects still gather millions of dollars from investors all the time.