TLDR - The Gitcoin Governance ecosystem is a fork of COMP/UNI.
At it's base layer, $GTC is a standard ERC20-style token with a 3mm supply, of which 50% has been awarded retroactively and 50% will be given to the community in the future.
At it's governance layer, $GTC is a delegated voting system which is forked from COMP/UNI. In the distribution of this token on 5/18, prospective holders play a delegation game in which they elected "Stewards" to make governance decisions on their behalf. By setting these defaults upon distribution, the $GTC aims to have high legitimacy by creating high voter engagement for proposals, and thereby creating the consent of the governed.
GTC will be used to bootstrap GitcoinDAO, an ecosystem of credibly neutral developer recruiting and public goods tools. Using GitcoinDAO, we aim to go to the Quadratic Lands, a place where public goods are funded, communities are stronk, and digital democracy reigns.
For more on GTC, please click here. For more on the technology behind GTC, read on.