The communication infrastructure of Canada is what you would expect for an industrialized country.
The international country code for Canada is 1. Area codes and local phone numbers are basically the same as used in the United States. (Three-digit area code, seven-digit local phone number). Some cities only require a seven-digit local phone number to place a call, but some cities require the three-digit area code.
Cell phones are widely used, but due to Canada's large size and relatively sparse population, some rural areas have only analogue service, or no service at all. Bell Mobility and Telus operate national CDMA networks and some regional providers operate in Saskatchewan, Manitoba and Atlantic Canada; Rogers Wireless operates the only GSM network, albeit under two brand names of Roger Wireless and Fido (the second GSM network operator, Microcell, was acquired by Rogers in 2004 and forms the base of the current Fido brand). GSM in North America operates on the 850MHz/1900MHz frequency bands, in contrast to the rest of the GSM world which use 900MHz/1800MHz. Travellers planning to bring their GSM phones with them might do well to check that their handset supports the appropriate frequencies. Wireless Internet access via GSM is prohibitively expensive.
There are many ways to access the Internet, including a number of terminals at most public libraries. WiFi access is common in cities. Most large and medium-sized towns will have internet and gaming cafes. Users can expect to pay $1-3$ CDN per hour for internet access as such establishments.
Of course, there is always the postal system. While its delivery times can be hit or miss (as quick as the next day in the same city to two weeks across country), Canada Post's domestic rates and service are more competitive than its American counterpart's. However, international parcel postal services can be costly. Postal offices are usually marked by the red and white Canada Post markings. Some drug stores, such as the Shopper's Drug Mart chain, Jean Coutu, Uniprix, etc., feature smaller outlets with full service. Such outlets are often open later and on weekends, as opposed to the the standard Mon-Fri 9:00-5:00 hours of the post offices.