What is the difference between implicit and explicit transactions?

Short answer: Implicit Transactions: Automatically begin when a database operation is executed. The DBMS treats each individual statement as a transaction and automatically commits after each statement, unless explicitly rolled back. Explicit Transactions: Transactions that the user manually controls using BEGIN TRANSACTION, COMMIT, and ROLLBACK. The user decides when the transaction begins and ends.

Real-world example (ShopNest)

Checkout wraps stock decrement + order insert in a transaction so you never sell stock you do not have.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.