Difference Between a Defect and a Bug in Testing

Depends entirely on the installation technology, company developing the software and the whim of the person using the terms. Generally though, updates stay within a product version (for example, hotfixes), while if you want to move to a later version, you would upgrade.

So you might install an update (hotfix) for Office 2007, or you might upgrade to Office 2010.

This page gives the definition according to Windows Installer: http://msdn.microsoft.com/en-us/library/aa370579(v=VS.85).aspx

An idiom is an idea to work around the quirks of a language. Some examples that come to mind are any of the C++ idioms you linked in the original question. They solve a common problem in that language in a canned way.

A design pattern is similar, in that it solves a common problem. But the ideal design pattern is based on common language features, and thus is language agnostic.

There is a continuum between idioms and design patterns, though, just as there is from low-level to high-level languages.

The Visitor pattern is a good example; if there were only one language that only supported single dynamic-dispatch, then we might consider the Visitor pattern an idiom of that language. But there are whole hordes of languages that don't directly support multiple-dispatch. Hence, the Visitor pattern was born.

The Observer pattern also comes to mind - C# directly supports it, so it doesn't need the common work-around form of the pattern.

An example going the other direction is OO features (inheritance, polymorphism, etc). C doesn't directly support them. If more languages were like C, then we might develop design patterns to implement v-tables, type-safety, etc. Since plenty of languages support those feature, we'd call any common solution in C an idiom, rather than calling the generalized solution a design pattern.