WinMerge is an Open Source (GPL) visual text file differencing and merging tool for Windows.It is highly useful for determing what has changed between project versions, and then merging changes between versions.

Features

* Visual differencing and merging of text files
* Flexible editor with syntax highlighting, line numbers and word-wrap
* Handles Windows, Unix and Mac text file formats
* Unicode support
* Difference pane shows current difference in two vertical panes
* Location pane shows map of files compared
* Highlights differences inside lines in file compare
* Regular Expression based file filters in directory compare allow excluding and including items
* Moved lines detection in file compare
* Creates patch files
* Resolve conflict files
* Shell Integration (supports 64-bit Windows versions)
* Rudimentary Visual SourceSafe and Rational ClearCase integration
* Archive file support using 7-Zip
* Plugin support
* Localizable interface
* Online manual and installed HTML Help manual