Push Notification
// Definition
A message delivered from a server to a client device or browser without the client polling — using APNs (iOS), FCM (Android/web), or the Web Push API. Testing concerns include: notification delivery when the app is in the foreground vs. background vs. closed, correct payload content, deep-link routing when the user taps the notification, handling of denied or revoked permissions, and notification grouping or badge-count accuracy. Also test what happens when the device is offline and comes back online.
// Related terms
Webhook
An HTTP callback that a service POSTs to a registered URL when an event occurs — Stripe payment succeeded, GitHub PR merged. Tests must handle delivery delays, retries, signature verification, and out-of-order events.
SMTP
Simple Mail Transfer Protocol — the standard protocol for sending email between servers. In a testing context, SMTP is the delivery layer beneath features like email verification, password reset, and notifications. Test concerns include: whether emails are actually sent (a stub or real SMTP endpoint must be in the test environment), correct recipient address, subject, body, and link content, and that sensitive tokens in email links are single-use and expire. Tools like Mailhog or Mailtrap provide a local SMTP server that captures outbound email without delivering it.