ROS is nothing but a middleware with a set of tools and software frameworks for building and stimulating robots. ROS follows a stable release cycle, coming with a new version every year on 23rd of May.
ROS released its Melodic Morenia version this year on the said date, with a decent number of enhancements and upgrades. Following are the release notes:
class_loader’s headers has been renamed and the previous ones have been deprecated in an effort to bring them close to multi-platform support and its ROS 2 counterpart. You can refer to the migration script provided for the header replacements and PRs will be released for all the .packages in previous ROS distribution.
Kdl_parser has now deprecated a method that was linked with tinyxml (which was already deprecated)
The tinyxml replacement code is as follows:
bool treeFromXml(const tinyxml2::XMLDocument * xml_doc, KDL::Tree & tree)
The deprecated API will be removed in N-turle.
For standardization reason, the OpenCV usage version is restricted to 3.2.
For more updates on the packages of ROS, refer to ROS Wiki page.