The official document permitting entry into and travel within Turkey. Is called Electronic Visa Turkey.
The e-Visa or Online visa is an alternative to stamps visas issued at Turkish missions and the ports of entry.
The visas electronically obtained after entering the required information and payments can be done by a credit or debit card (Mastercard, Visa, or Over Mail order).
The eVisa system will email the printed document to you to inform you that your application is completed successfully. Passport control officers at the airports of entry can verify your e-Visa on their system. However, keep your soft copy (tablet PC, smartphone, etc.) or hard copy of your e-Visa with you if any failure on their network.
As in other visas, respective Turkish officials at the ports of entry reserve the right to deny entry into Turkey to a holder of an e-Visa without any explanation.