Hot swapping can also refer to the ability to alter the running code of a program without needing to interrupt its execution. Interactive programming is a programming paradigm that makes extensive use of hot swapping, so the programming activity becomes part of the program flow itself.
Only a few programming languages support hot swapping natively, including Pike, Lisp, Erlang, Smalltalk, and Java. Microsoft Visual Studio supports a kind of hot swapping called Edit and Continue, which is supported by C#, VB.NET and C/C++ when running under a debugger.
them on the fly. However, although the same as hotswapping for most intents and purposes, this is technically just a cache purge, triggered by a new file. Note that this does not apply to markup and programming languages such as HTML and PHP respectively, in the general case, as these file are normally re-interpreted on each use by default. There are a few CMS's and other PHP-based frameworks (such as Drupal) that employ caching, however. In these cases, similar abilities and exceptions apply.
Hot swapping also facilitates developing systems where large amounts of data are being processed, as in entire genomes in bioinformatics algorithms.
Read more about this topic: Hot Swapping