For years marketing experts and technologists have been predicting the death of email due to the rise of social media and messaging apps, but email is not dying. According to the 2017 M+R Benchmarks study of nonprofit digital advocacy, 26% of all revenue raised online comes from email, and email revenue grew 15% in 2016 over 2015. Email engagement consists of two basic message categories that need to work in harmony to succeed: Newsletters and…