C++ FAQ Celebrating Twenty-One Years of the C++ FAQ!!!
(Click here for a personal note from Marshall Cline.)
Section 27:
[27.12] Which is better: identifier names that_look_like_this or identifier names thatLookLikeThis?

It's a precedent thing. If you have a Pascal or Smalltalk background, youProbablySquashNamesTogether like this. If you have an Ada background, You_Probably_Use_A_Large_Number_Of_Underscores like this. If you have a Microsoft Windows background, you probably prefer the "Hungarian" style which means you jkuidsPrefix vndskaIdentifiers ncqWith ksldjfTheir nmdsadType. And then there are the folks with a Unix C background, who abbr evthng n use vry srt idntfr nms. (AND THE FORTRN PRGMRS LIMIT EVRYTH TO SIX LETTRS.)

So there is no universal standard. If your project team has a particular coding standard for identifier names, use it. But starting another Jihad over this will create a lot more heat than light. From a business perspective, there are only two things that matter: The code should be generally readable, and everyone on the team should use the same style.

Other than that, th difs r minr.

One more thing: don't import a coding style onto platform-specific code where it is foreign. For example, a coding style that seems natural while using a Microsoft library might look bizarre and random while using a UNIX library. Don't do it. Allow different styles for different platforms. (Just in case someone out there isn't reading carefully, don't send me email about the case of common code that is designed to be used/ported to several platforms, since that code wouldn't be platform-specific, so the above "allow different styles" guideline doesn't even apply.)

Okay, one more. Really. Don't fight the coding styles used by automatically generated code (e.g., by tools that generate code). Some people treat coding standards with religious zeal, and they try to get tools to generate code in their local style. Forget it: if a tool generates code in a different style, don't worry about it. Remember money and time?!? This whole coding standard thing was supposed to save money and time; don't turn it into a "money pit."