[pbreit]

Most individual investors, including younger, should have little or no money in individual stocks but instead in something like a Vanguard diversified portfolio of cheap index funds/ETFs. If you want to take 5% or 10% of your worth to the stock casino, sure (after paying off all your credit cards and maxing your 401k/IRA).

[icedchai]

I do both. I have about 20% of my net worth in individual stocks, the rest in low cost index funds/ETFs.

The biggest gains and losses, of course, obviously come from individual stocks (and options, if you're feeling brave.) You're not going to see triple digit yearly returns with a mutual fund. You might find it on the next SaaS growth stock.

When you're young, you should absolutely take on some risk. (That includes working at startups!)