Что такое RTA??
RTA - real time attack, is a time that took player to beat game. Does include load time.
Also RTA means kind of runs, which is: allowed save/loading, but you have to beat game in one sitting. Single-segment basically is the same, you also have to beat game in one sitting, but save/loading is disallowed.
From that Segmented is a kind of run which segments (different moments of one run) are being done in different moments to get better results.