There are actually 91 errors described in the article, but number 90 looks nicer in the title. The article is intended for C/C++ programmers, but developers working with other languages may also find it interesting.
The materials collected in this article will be useful for authors of articles, books and blogs. Examples of errors can be used to demonstrate advantages of different programming styles – for instance, why you should not try to make your code shorter by writing long expressions.
You can read the article here: PVS-Studio advertisement - static analysis of C/C++ code.