There are infinite ways to attain the goal of self-realisation.
18 yoga paths were discussed as separate chapters in Bhagavad Geeta, sacrad book of Hindu philosophy.
These paths should not be misled/misunderstood by the names used by some organisations (as trade marks) like Raja yoga (of Brahma kumaris’) sahaja yoga, siddha yoga transcendental meditation (TM) etc.
Each one of these paths are self-contained. Some of them uses other yoga techniques for fast and easy progress. Each one of them have their own merits and demerits.