Will there be enough bitcoins?
Yes.
I read that there are only 21 000 000 bitcoins. Of these bitcoins, only 13 000 000 have been released by the system.
Correct. There are 13 252 000 released so far. The remaining 7 748 000 will be released between now and the year 2140.
That Satoshi person, has a few million and he is not spending it.
That's an assumption. It may not be accurate.
Lots of other bitcoin whoreders [Is that the right word] keep the bitcoins for themselves.
I think the word you are looking for is "hoarders". Most hoarders will eventually spend and use their bitcoins.
So only a few bitcoins are in circulation.
In Africa, their are 14 000 000 000 000 people. I each of them, has only a few satoshis, nobody else will have any coins.
You are mistaken.
There are only approximately
7 243 000 000 people in the entire world therefore there cannot be
14 000 000 000 000 people in Africa.
How do they over come this problem? [People on other forums says by increasing the decimal value = 0.0000000000]
How does that work?
13 000 000 bitcoins. Each bitcoin is 100 000 000 satoshis.
That means there are 1 300 000 000 000 000 units of currency available.
1 300 000 000 000 000 satoshis / 7 243 000 000 people = 179 483 units of currency on average for every human being on the planet.
That assumes that every human (including infants) is actively participating in bitcoin and that there are no other currency systems in existence on the entire planet.
More than likely there will be many infants and other humans that do not participate in the bitcoin economy at all. This means that each active participant in the bitcoin economy could have several hundred thousand satoshis.
As the number of bitcoins increases during the next 100 years, the average number of satoshis per active participant will increase perhaps to a million of more.
It appears there is not a problem with the quantity available.