Canadians are getting a few new area codes to meet increasing demand motivated by population growth and a boom in wireless technology.

Mobile phones, tablets and applications – which also communicate with other machines — are all assigned their own phone numbers.

With only about 7.5 million numbers possible for each area code, it’s understandable they may run out in heavily populated areas.

With that, here are five things you may not know about area codes:

1. When did they start?

Area codes were first introduced to Canada as part of the North American Numbering Plan (NANP) in 1947, in order for people to make long-distance calls themselves instead of needing an operator. By the time area codes were used, Canada had nine.

The NANP now serves 20 countries: Canada, the United States and some in the Caribbean. U.S.-based AT&T developed the plan, giving each province one number — with the exception of Ontario and Quebec, which had two each.

Here is a list of all the numbers, their date of creation and from where they were split.

2. How do they work?

All numbers within these NANP countries have 10 digits: The area code holds the place of the first three digits. Area codes must start with numbers between two and nine.

The area code is followed by another three numbers, referred to as Central Office Codes (CO codes), which also must start with a number between two and nine.

In a 10-digit number, there are a possible eight million phone numbers; however, about 50,000 of those are not usable for various reasons (think 555 numbers or numbers that have a digit followed by 11.) That leaves approximately 7.5 million numbers available for each area code.

When number prefixes (the area code + CO code) run out, there is a need for a new area code.

Glenn Pilley, director of the Canadian Numbering Association, said that from about 1960 to 1990, there were no new area code numbers needed in Canada.

"In 1998, we started adding more and more until the Toronto ones were done in 2001," Pilley said. "Then it was quiet for a while, because I think the recession in 2001 had an effect on the growth of things, including the telecom industry."

Now, as demand for cellphones and other mobile devices grows, the Greater Toronto Area will get two new area codes in March. Manitoba will get a new number in November and British Columbia will get one more sometime in 2014.

When all those numbers are implemented, Canada’s total number of area codes will be at 31, where Pilley expects it will remain for the following two to four years.

3. How are they chosen?

In 1947, AT&T chose the easiest and shortest number combination (212) when dialing from a rotary phone for New York City. Another easy and priority number was given to Washington, but Pilley assures that the rest of the numbers were randomly given out.

Dealing out numbers now is a complicated mathematical process, involving the creation of a complex 11-page spreadsheet that is fed a mathematical formula. It’s given a list of unassigned CO codes and then drops out a randomized number that works.

4. Will we run out?

Currently the NANP is doing everything it can to conserve and optimize the numbers in use in order to put off that inevitable fact.

Pilley estimates that by 2042 — less than 30 years — we will run out of usable area codes.

"The NANP is scheduled to run out around 2042," He said. "That’s partially because it’s common for each person to have two to three personal numbers, and because of this new machine to machine thing going on, with applications on various machines using cellphone frequencies."

5. What’s next?

There are a few possibilities of how the industry will handle running out of area codes.

"In 1999-2000, the industry got together and advised a plan for when they would run out of numbers," Pilley said. "They submitted a plan to all governments in the NANP which has yet to be approved."

The plan was either to add another digit to area codes, making them four digits, which would then take the possible numbers within each area code from 750 to 7,500. Or, they could add another number to the central office code — making that one four digits, with the same result.

According to Pilley, some have advised both changes be made at once, making 10-digit phone numbers into 12-digit numbers.

Of course, since that time, there has been the advent of VOIP (voice over internet protocol), a procedure that allows for telephonic communication through the internet.

"New companies use computer-based switches, which are way less expensive, " said Pilley.

"The whole industry is looking at conversion to VOIP. Some people say it could happen as early as 2018, I think it’s maybe a few years after that, but it does look like it’s coming."