If you are applying for a visa through online you will be getting the visa as a PDF which can be printed and shown at the border once you reach the border of Iran. This Iran visa, however, will not be stamped onto your passport nor will there be a sticker attached on your passport. This decision was taken by the Iran government after knowing that the stamp can affect the tourists from travelling to other countries. This will be done even if you apply for a visa through an embassy.