Compare Suite can compare both - related and non-related files.
"By keywords" comparison feature highlights common and unique keywords, allowing to compare non-related files.
"Word by word" comparison compares files with a common ancestor.
If you work with plain text, then you can edit compared documents, apply or decline changes.
Finally, you can bring comparison details to simple or advanced structured report.

Compare, view, synchronize and merge files from various folders very easily with this tool. See the differences and copy lines from one file to another instantly. Perfect for programmers who want to compare source codes in many languages. Compare files according to many rules like size, modified date, created date...

Files Compare is a visual tool for files and directories comparison. It helps you to compare and merge different versions of the same textual file. A color-coded side-by-side comparison makes it easy to understand differences between two files at a glance, powerful editing engine helps you to merge found changes and edit text directly. Program has a number of simple and convenient features that many users have been expecting for a long time.

A must have for those who often deals with identifying files that have been changed.
New IsEqual will help you to quickly identify differences between files even with multitude of new features. IsEqual will do it in the most informative way - visual. Those parts that have been added or removed will be marked in different colors.
IsEqual will satisfy all your file compare and file merge tasks.

SwiftCompare is a utility to Compare Files and Folders and Merge/Synchronize the differences between them. What makes SwiftCompare distinctive is the presence of a very customizable Compare and Merge engine(CME), allowing the user to Compare and Merge/Synchronize Folders and Files the way he likes. SwiftCompare can be used to Manage Source code, keep Folders in Sync, Verify Data, Restore corrupt Data, and much more.

Code Compare is an advanced comparison and synchronization tool that compares text, source code, XML files and directories then, highlights differences and merges content via its visual interface. Code Compare can make version comparing and code reviews a much easier process.

NH's PictureSort is a easy to use program to view, flip, rotate, compare, sort, rename and categorize pictures and other files. Within one single program, you can view, flip, rotate and compare pictures, move one or more pictures to new folders and rename one or more pictures with only a few mouse clicks. And of course you can move and categorize all other files too. All work is done in dialog with the user.

This program can compare and find similar (duplicate) MP3, WAV files. Files compared by content, ID3 tags and file names.

Snapper reads the directory of a disk which is then saved as a "snapshot", so that later you can compare it with a new snapshot of the disk and see what has changed. The results are easy to see with colour-coded highlighting in a familiar Explorer-style interface. Print the results, or export them to create a customisable batch file or installation script. Extremely quick to use and to learn.

AJC Directory Synchronizer makes it easy to synchronize files and compare folders between any two locations. Synchronize large numbers of files between computers, sync laptop to desktop, mirror to backup drive, sync mp3 player etc.

Wizards make it very easy to setup your synchronize task which can be saved as a project for quick regular use. Built in archiving system makes it easy to recover files if you make a mistake.

Detailed System Info - Create & Store Notes - File Finder - File Indexer - Compare Files & Find Duplicate Files - Create Virtual Folders - Auto OR OneClick Backup - Dual Pane Windows Explorer - Image Viewer in Gallery, Film Strip or Slide Show formats - Hot Keys - Disk Catalogs of HDD, CD, DVD, Floppy, USB Disks - File Shredder - Password Manager - 19449 File Extensions Info - Quick Launch shortcuts of applications, files, folders, URLs

ComponentSoftware HTMLDiff (CS-HTMLDiff) is an advanced file-difference analysis tool for Microsoft Windows which analyzes & presents differences in HTML, XML, MS-Word and text documents.

Changes to HTML files may be viewed visually as they appear in your browser, or you can analyze the changes at source level.

CS-HTMLDiff even lets you compare online documents !!

CSHTMLDiff is a powerful ActiveX control which allows you to compare two revisions of a file visually in a quick, easy and friendly way.
CSHTMLDiff utilizes a robust engine that recognizes various file types, including Text, XML and HTML. The engine can be easily configured for most kinds of comparison settings.
Files can be compared either locally or over ftp/http protocols.