It can not only compare text documents but also folders. Text documents in this case means any document that can be loaded and displayed in a text editor like Notepad. Two documents can be loaded into the software program. These documents are then displayed in two panes in the interface where they can be compared with each other. The program will automatically display differences visually which makes it easy to spot differences in the documents.

Lines that have been added, deleted or modified will be displayed in their own distinct colors with the possibility to change these colors in the settings. The document comparison tool can be configured to ignore blanks and case differences as well. It is possible to edit the documents manually or by using the search and replace functionality in the top menu.

It is furthermore possible to split the documents vertically instead of horizontally which might make sense on computer systems with smaller computer monitors and lower resolutions. Several keyboard shortcuts are available to jump between differences in the documents. TextDiff is a handy portable document comparison software program.

The user has to create an account with the service to be able to log into the software. Once logged in it is possible to add documents, the software is able to work with the formats txt, doc, rtf and html – and compare these documents against local and Internet resources.

Local resources can be selected by adding folders to the plagiarism checker. The contents of the folders will be analyzed. It is possible to submit the contents to an online database by clicking on the Publish button. This is however not a requirement. The benefit of publishing the data is that documents scanned by other users will be compared to those documents. The process is rather unclear as there are no information about the data that will be submitted in that process.

Searching the Internet for similarities to documents that have been added in the first step is the last option of the plagiarism checker Viper. It is again unclear how and where the search is performed. Results will be shown in the end. Documents that have been discovered in the process will be shown with ratings to make it easier for the user to identify how similar they are to the original documents. Reports can be saved in the end to archive the results.

The number one reason to use Viper is probably to check local documents against other local documents as this is the only transparent process of the plagiarism scanner. Internet search could probably also be conducted by simply entering a few sentences of a document into a search engine (don’t forget the “”).