C++ FAQ Celebrating Twenty-One Years of the C++ FAQ!!!
(Click here for a personal note from Marshall Cline.)
Section 5:
[5.7] What makes a good Subject: line?

Be descriptive:

  • Bad: "Subject: HELP"
  • Bad: "Subject: C++ problem"
  • Bad: "Subject: SEX SEX SEX"
  • Good: "Subject: Problem new'ing a multi-dimensional array"

Mention your compiler/version if you think it's relevant.