3 ms·

Mozilla, Firefox, Chrome, Safari, and I think one of the IE's too. And now this. So yeah, 5-6 is a good estimate. Edit: Also the original Netscape.

• fzzzy 14y ago
  None of those were from the ground up. Mozilla was based on the netscape codebase, firefox was based on the mozilla codebase, safari was based on the khtml codebase, and chrome was based on the webkit codebase. IE I'm not sure about, but it seems unlikely that they started from the ground up, surely newer ie uses code from older releases.
  • lifthrasiir 14y ago
    Unless there are actually multiple layout engines developed by Microsoft. At least three (Trident, Tasman and some other used by Expression Web) of them are known, and it is entirely possible that they don't share the common codebase.
  • fpgeek 14y ago
    You're right. Internet Explorer was originally based on Spyglass Mosaic. [1] [1] http://en.wikipedia.org/wiki/History_of_Internet_Explorer http://en.wikipedia.org/wiki/History_of_Internet_Explorer