Internet, Web, and Other E-Issues

Q. I could not find the term “dot-com” addressed, and I need to know how to capitalize it and punctuate it. I have seen both dot.com, and dot-com. Which is correct? In capitalizing titles, is it Dot.com or Dot.Com (in title headings, etc.)?

A. We write “dot-com”: dot-com fantasies. We do not write “dot.com”—that would read “dot dot com.” In titles, capitalize the d and the c: “Mogul’s Dot-Com Dreams Leak Like RAM from a Cheap Chip.”

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]