What is the "Variations" section in the output of "about:version" or "chrome://version" in Google Chrome for Linux?

Question

Google Chrome 24.0.1312.56 (Official Build 177594) on Ubuntu 12.04

When I type chrome://versions or about:versions in the address bar and hit Enter, the output includes a section called "Variations" that looks like this:

5666f941-fd526c81
b03ddc1f-2d9ef0cc
4dcb0cd6-d31c4ca1
f9b252d0-fd526c81
ccee547a-766fa2d
571ffcab-766fa2d
60f3499f-766fa2d
76b86d80-766fa2d
ffbe45b6-dbbd7415
75f7fb7e-766fa2d
24dca50e-837c4893
ca65a9fe-91ac3782
9c097cbc-d00c3f8d
3028188e-d60b5a5f
df910896-3d47f4f4
5a3c10b5-e1cc0f14
244ca1ac-4ad60575
246fb659-4ad60575
f296190c-bd104136
4442aae2-6e597ede
75f0f0a0-e1cc0f14
e2b18481-6e3b1976
e7e71889-e1cc0f14
980cfc4b-e3130bf3  

Can anyone please explain, even in general terms, what those lines mean or refer to?

Solution

This answer below is based on the answer to a question asked at stackoverflow: What is following header for: X-Chrome-Variations?.

To improve the performance of the browser, Google tries new ideas out in the real world to discover useful features. These are called Field Trials.

The "Variations" section seen in the output of chrome://version is a part of Google's Field Trials. Users of the Release version of the Chrome browser can see a series of hash-hash pairs in the "Variations" section of chrome://version since Chrome 23.

More information on the purpose of Chrome Variations can be found in Google Chrome Privacy Whitepaper; the relevant section is quoted below:

To help guide the construction of features that users actually find useful, a subset of users may get a sneak peek at new functionality before it’s launched to the world at large. The field trials that are currently active on your installation of Chrome will be included in all requests sent to Google servers to allow Google to filter logs for only those generated by a given variation of Chrome. This Chrome-Variations header will not contain any personally identifiable information, and will strictly describe the state of the installation of Chrome itself.

The variations active for a given installation are determined by a seed number between 1 and 8192 (13 bits of entropy) which is randomly selected on first run. If you would like to reset your variations seed, run Chrome with the command line flag --reset-variation-state.