To visit Toronto, you must have at least a six month valid passport. Intended tourists must also be in good health and satisfy an immigration officer that they will leave Canada at the end of their visit, and that they have enough funds for the duration of their stay.
The visa may be a single entry Visitor Visa- valid for 6 months only allowing you to visit Canada once.
A Multiple Entry Canadian Visitor Visa allows you to enter and depart Canada on many occasions and is valid for up to 6 months.
Temporary Resident Visas are also given, depending on your citizenship, a medical examination and a letter of invitation from a Canadian resident must be provided.