Email Glossary

OTP/Verification Email

An OTP (One-Time Password) email contains a temporary numeric or alphanumeric code used to verify the recipient's identity. OTPs are commonly used for two-factor authentication during login, verifying new account creation, and confirming sensitive actions like password changes or wire transfers.

OTP Best Practices

Use 6 to 8 digit codes that are difficult to guess. Expire OTPs within 5 to 15 minutes. Allow each OTP to be used only once. Rate limit OTP requests to prevent abuse. Do not include the OTP in the subject line or expose it in logs. Consider alternative channels like SMS for security-sensitive applications.

Related Terms

Password Reset Email

A security email sent when a user requests to reset their password, containing a time-limited link to complete the reset.

Transactional Email

Automated emails triggered by user actions like password resets and order confirmations.

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