Objective - A milestone on the Lisk roadmap. It describes the overall intention of that particular point of development. An objective can be changed based on the outcome of its LIP process.
Phase - A distinct period in a process of change during Lisk's development, generally focused on particular objectives or LIPs such as improving Architecture, or Network Economics.
Roadmap - A roadmap is a strategic plan that defines Lisk’s goals (Blockchain Application Platform, Sidechains, SDK etc.), that includes the major phases and objectives needed to reach it.
Technical debt - A concept in software development that reflects the extra development work that arises when code that is easy to implement in the short run is used instead of applying the best overall solution, that may require more time and effort.