I understand the basic meaning.. but what I dont know is what exactly IS high?
50 % growth? 100 % growth etc?

It means buy when the price is low and sell when the price is high. High depends on what you paid for it, what people can anticipate about the future prospects, and what the market has in store.
It also depends on how long you are going to have the money in there i.e. a 20 yr old does not have to freak out he has 40 more years for his stock to grow and he hopes for the best. A person with only two more years to retire may want to cut his losses and pull out and save what's left.

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The political system is broke and it's a joke.

I don't think you can put a specific number on "high" in this case.
If I by stock for $1.50, and it goes up to $25, then goes down to $12.50, but then rebounds to $24.50--you've made a huge profit, whether you sold at $25, $12.50 or $24.50.

Some stock is pretty stable(and are good investments), others are so-so and could pay off big if you time it just right. Others will hit an "all-time" high, and then bottom out for less than what you paid for it. If you didn't sell when it was high, you lose; sometimes, you lose a lot!

I don't like the stock market, because I'm too chicken to "gamble". I lost $60 in Vegas and nearly cried! (even though I had brought substantially more money with me, I just couldn't gamble anymore after that!)

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Mental that one, I'm telling you. ---Ron Weasley, "Harry Potter and the Chamber of Secrets"

Marylin I know how you feel I tell my husband rather than going to the casino I will go to the store where when I swipe my card I get a prize every single time! It was kind of fun when we used to put coins in but now....

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The political system is broke and it's a joke.

Oh yeah! I can guarantee that if I take $60 to Target or Ross or Macy's I will find something much more fulfilling; as opposed to realizing I just LOST that money and will never see it again! At least when I shop, I have something pretty to look at when I'm done!

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Mental that one, I'm telling you. ---Ron Weasley, "Harry Potter and the Chamber of Secrets"

Playing the stock market seems to become an actual job for those who really get into it. I'm not a gambler either. I prefer to have my money in an account that grows slow and steady over years and years... Very safe investments. But that's me. I've heard of people getting really rich by playing the stock market. More power to them!