In the majority of cases visas are stickers placed into your passport. They take the whole passport page and have a whole array on information, such as the country name, your name (sometimes also a photo) and visa validity dates.
Electronic visas (eVisas) are uploaded on your order once they have been approved. They then need to be printed out and taken on the trip with you. We'd recommend taking a few copies - you might encounter multiple officials that wish to see a copy, or you might not come across a printer should you lose it!
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