1. What is a redline?

A redline (a.k.a. a blackline) is a document that shows how one document was modified to become another document. The deletions in the original document is shown as a red strikethrough text, whereas insertions to the original document is shown as a blue underlined (sometimes double underlined) text. Moved text appear in green, with strikethrough showing the original location, and underlined text showing the new location. Stated differently, the redline represents two documents in a single document, while stylistically highlighting the differences between the two.

This practice of representing two documents in one is very useful for editing and reviewing when revising a document ("What ended up changing?"), and also when negotiating a contract ("Which proposed changes are acceptable/unacceptable?"). As such, legal industry has long utilized redlines. In the old days, people used to create redlines by hand, which took substantial time and effort to do, not to mention it containing myriad of errors. However, computer algorithms were developed to automate the process, and it represents one of the first instances of wide-spread adoption of technology that is specific to law in the legal industry.

2. Which document formats are supported here?

Redlines.com supports most document formats, including:

3. What does the redline app do exactly?

The redlining process, at its core, begins with a form of Levenshtein Distance, which measures the differences between two texts by number of changes required to make one into another, and displaying the actual character-by-character differences. The raw results are difficult to read by a person, because the redline is done at a 'character' level, instead of at the 'word' level. A second algorithm is necessary to convert the character-level redline into the word-level by adding filler text, thereby improving the readability of the redline. For example, if the word "hello" became "help", a character-level redline would show hello p and the word-level redline would show hello help (which is longer than the character-level redline in total length due to the bifurcation of "hel" into "hel" and "hel ", creating a juxtaposed text). In addition, the Document is simultaneously analyzed to see if these changes are better described as 'movements'.

4. Microsoft Word already has a Compare function. Why do I need it?

There are numerous reasons why a user may want to use a web based application to redline a document. First, Microsoft Word might not be installed in the device you are using, which is becoming more common in the increasingly mobile-centric world, especially given the popularity of Linux. You might also have versions of MS Word that does not have such features (such as Microsoft Word 2011 for Mac), or a version that is only capable of displaying the result in track changes mode, or use a different word processing software altogether. Second, redlines.com supports more formats than MS Word for redlining. Third, redlines.com is capable of 'changed pages' only mode where only pages containing changes are compiled in the PDF, which is not available for MS Word. Fourth, our algorithm shows the 'movement' of text in green, which is important for practitioners but not included in the MS Word's compare function. Finally, you can open multiple tabs of this web app and run many redlines all at once (parallel processing instead of serial processing).

5. How long does redlining take?

It depends on the length of the document but it typically lasts only a few seconds, and for longer documents, a few minutes. If you are familiar with the existing process, the time it takes is very similar to running it on your desktop. However, because this is a web-based application, please note that additional time may be required for upload and download.

6. Are there any limitations on the free comparison?

To manage costs relating to computing processes, we currently limit the file sizes of original and modified documents to 4MB combined, and the resulting redline to 4MB. The total redlining processing time is limited to 5 minutes. If you have any pictures or graphics in the document, you should remove them to reduce the document size.

7. How secure is your website?

Our app is designed by an experienced attorney who understands that documents come with both information and responsibility. We utilize the industry standard SSL encryption so that the communication between the server and client browser remains private. We never save any file onto a disk, and any document within the computer memory is immediately purged upon completion of the redlining process. Our goal is to eliminate any possibility of document retention since such procedure exposes us to risks and increased server maintenance costs. And we never share any of our customer information to third party vendors for marketing - we hate spam just as much as you do!

8. How do you make money?

We rely on sponsorships and private server deployments.

9. How do I reach you? I have other questions.

Please send general inquiries to info@celant.com.