Earn Money online? Is it a scam or not?

We have all heard at some point about these websites claiming that you can earn a lot of money just by signing up to their websites, are these scams? Or is it really possible?

First and before anything else we need to understand what money is, seems like a joke to you, but unfortunately a lot of people falling for scams are people convinced that money is something that can be earned for free, now back to the point, before money was invented people used to trade, for instance someone who have a wheat farm, and needs to buy some clothes would give another guy an amount of wheat in exchange of clothes, when time passed and populations began to grow this method proved to be very ineffective because of how volatile products can be, for instance a farmer will need to continually trade his wheat, otherwise it will expire, not to forget about parasites that can destroy an entire stock of wheat turning the wealthiest into the poorest. And also the difficulty of controlling markets and prices emerged so people had to come with another type of trading item that could be unified across the nation and be as stable as possible, so they came up with money (They were gold coins before money but that's another story) in other words the only way to buy or sell something has always been by giving something in exchange of another, nowadays we may not be trading items for items, but we do trade money in exchange of items. That's why the bank doesn't give free money, you need to give it something to give you money (gold in this example), same with your job, the place you work at doesn't give you money for free, you need to work, which is time + effort + your education put in exchange of money, when you have given these, they give you money, which you can exchange with goods, etc...

Now what?
As you have seen free money is the equivalent of a guy living in the era before money was invented, and a bag of wheat falling from the sky, it's IMPOSSIBLE so is free money!
No one will give you free money, you need to give them something before they can give you money. And that's the first main point you need to retain on order to be able to identify a scam:
What am I giving in exchange of this so-called free money?

For instance You see that YouTube claims to give channel owners money, can you identify whether it's a scam or not?

What does YouTube asks in exchange of money? They are asking for views of their ADS.
YouTube is exchanging views of ADS on your channel for money
So we can safely assume that YouTube is not scamming people and that it is indeed going to give people money.

So to answer that question in the title, It's indeed possible to make money online or in other words it's possible to exchange something with money on the internet, whether it's time and effort to upload videos on YouTube or it's a Crypto-Currency miner that takes the computing power of your computer, or it's a faucet that needs you to click on a couple of ADS, there will always be something in return for that money. So yeah you can say goodbye to these websites claiming that after signing up you will be given 1trillion$ XD.

So to summarize, earning money online isn't a scam, and a lot of big companies/services like Google, Uber, Steemit, YouTube and many other companies are offering to earn money online and they are legit, but that doesn't make any website that offers similar benefits legit, so it's always a good idea to apply this method to be able to differentiate at first glance the scam and the legit, but don't forget that doesn't mean that a website operating with this scheme is legit, and always make sure to search about the websote and ask people who have previously used it, in order to get the most accurate answer on whether it's legit or not.

Beaware though that some scamming websites may still ask you for tasks in exchange of money and still screw you over, so it doesn't mean that a website operating with the same scheme I described above is legit, the scheme I described is not a full guide on how to detect fake and scamming websites, You should always google a website before investing time, effort or money in it, it's always important to get the advice of experienced users who dealt with that website or service before.