1# 12\. Document Changelog 2 3For a summary of changes to the Compatibility Definition in this release: 4 5* [Document changelog](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/?pretty=full&no-merges) 6 7 8For a summary of changes to individuals sections: 9 101. [Introduction](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/1_introduction?pretty=full&no-merges) 111. [Device Types](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/2_device_types?pretty=full&no-merges) 121. [Software](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/3_software?pretty=full&no-merges) 131. [Application Packaging](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/4_application-packaging?pretty=full&no-merges) 141. [Multimedia](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/5_multimedia?pretty=full&no-merges) 151. [Developer Tools and Options](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/6_dev-tools-and-options?pretty=full&no-merges) 161. [Hardware Compatibility](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/7_hardware-compatibility?pretty=full&no-merges) 171. [Performance and Power](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/8_performance-and-power?pretty=full&no-merges) 181. [Security Model](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/9_security-model?pretty=full&no-merges) 191. [Software Compatibility Testing](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/10_software-compatibility-testing?pretty=full&no-merges) 201. [Updatable Software](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/11_updatable-software?pretty=full&no-merges) 211. [Document Changelog](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/12_document-changelog?pretty=full&no-merges) 221. [Contact Us](https://android.googlesource.com/platform/compatibility/cdd/+log/CURRENT_BRANCH/13_contact-us?pretty=full&no-merges) 23 24## 12.1\. Changelog Viewing Tips 25 26Changes are marked as follows: 27 28* **CDD** <br>Substantive changes to the compatibility requirements. 29 30* **Docs** <br>Cosmetic or build related changes. 31 32For best viewing, append the `pretty=full` and `no-merges` URL parameters to your 33changelog URLs. 34