attachments

In computing, an attachment is a file which is attached separately to a message that you send to someone.
When you send an email you can also send a file as an attachment and that file can be a graphic, a program, a sound or whatever. Source: Collins Dictionary

Attachments can be harmless (e.g. photos of your cousin)…

Attachments can also be hazardous (e.g. executable files that can install malware onto your device)…