When one checkmark appears in WhatsApp, what does it mean - briefly?
When a single checkmark appears next to your message in WhatsApp, it indicates that the message has been successfully sent from your device but not yet delivered to the recipient's phone.
When one checkmark appears in WhatsApp, what does it mean - in detail?
When a single checkmark appears on a message in WhatsApp, it indicates that the message has been successfully sent from your device to WhatsApp's servers. This is the first stage of message delivery and confirms that the message has left your phone. However, it does not guarantee that the recipient has received the message yet. The single checkmark is merely an acknowledgment that your message is in transit and will be delivered once the recipient's device is online and connected to WhatsApp's servers.