The four everyday electronic fund-transfer rails in India: how RTGS (real-time gross) differs from NEFT (deferred net), what IMPS and UPI add, who operates each, and the legal and institutional backdrop - the PSS Act, 2007 and NPCI.
Reading the 10 sections above, the worked examples and the practice set is free — the whole knowledge base is on the free plan, along with flashcards, private notes and Ask Onely.