These are targeted and simple forms of phishing emails designed to get victims to purchase gift cards, or to give up personal email or phone numbers. The "email compromise" gets its name because the attacker mimics the email of a known sender. However, these can also be sent through a legitimate, albeit hacked account. The messages start out as basic greetings then progress into requests for money or data. Since the content is highly personalized it’s often easy to get hooked.