In episode 42, I recommend having the e-mail subject line summarize the message rather than describe the message.
Reader Lee asked an excellent question: What if you're replying to someone else's message? Do you rewrite the subject to summarize your response, or do you leave the subject the same?
If you're replying but changing the topic or starting a new conversation, change the subject line to something summarizing the new conversation.
If you're replying to a message and keeping the topic mostly the same, leave the subject line alone. That way, it shows up as being the same conversation in the recipient's email (Gmail and Thunderbird both identify conversations by subject). If the subject line is something utterly non-descriptive (“hi!” or “okay”), however, you may still want to change it to something better.
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