Why did the colonists criticize the stamp act as taxation

The Stamp Act was enacted to cause the colonists to pay the tax. This was represented by the stamp on various kinds of documents and papers. The colonists actually criticized the Stamp Act by calling it as taxation without representation because the government cannot generate tax without showing representation of goods and services in the Parliament. This lead to the adverse colonial reaction to this Act caused the boycott of British goods. This was also associated with the riots and attack of colonists over the tax collectors.