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Where do you think your money goes when you are "Buying a stock you know nothing about based on a tip from a friend? ... Day trading? ... [using] Junk bonds? ... [using] Hedge funds"
When you do any of those things you are "Putting your money in the market" yet you label that last one "investing" and the others "betting". Investing IS betting, how safe the bet is is the only distinction there. You call the safest bet "Investing" and the riskier ones "betting". They're all just different points on the same scale.
I would say that you're "investing" when you research a company, believe it can use your money well and wisely and buy its stock (or bonds or make use of another transaction). That's still betting, but at least there the intention is slightly different than a mere weighing of risk. Anything else is a bet through and through.