A regulation to the Income Tax Act (Canada) sets out exactly what has to be included in an official donation receipt issued by a Canadian registered charity.  Here is the list:

http://www.cra-arc.gc.ca/chrts-gvng/chrts/prtng/rcpts/whtnf-eng.html

“What information must appear on an official donation receipt?

All official donation receipts for income tax purposes must contain the following:
• a statement that it is an official receipt for income tax purposes;
• name and address of the charity as on file with the Canada Revenue Agency;
• charity’s registration number;
• serial number of the receipt;
• place or locality where the receipt was issued;
• day or year donation was received;
• day on which the receipt was issued if it differs from the day of donation;
• full name, including middle initial, and address of the donor;
• amount of the gift;
• (under proposed legislation) value and description of any advantage received by the donor;
• (under proposed legislation) eligible amount of the gift;
• signature of an individual authorized by the charity to acknowledge donations; and
• name and Web site address of the Canada Revenue Agency – www.cra.gc.ca/charities.
For non-cash gifts (gifts in kind), these additional elements:
• day on which the donation was received (if not already indicated);
• brief description of the property transferred to the charity;
• name and address of the appraiser (if property was appraised); and
• (under proposed legislation) deemed fair market value of the property in place of amount of gift above.
For examples of receipts, see Sample receipts.
Related topics
• Registration number
References
• CPC-010, Name on Official Donation Receipt
• CPC-015, Address on Official Donation Receipt
• RC4414, Registered Charities: What’s New? – Important Changes to the Law Affecting Registered Charities”

Practically speaking if you want to see what an official donation receipt looks like check out the sample official donation receipts CRA http://www.cra-arc.gc.ca/chrts-gvng/chrts/pbs/rcpts-eng.html