The ship struck an iceberg at 11:40 p.m. (ship's time) on Sunday evening April 14, 1912, and sank two hours and forty minutes later, after breaking into two pieces, at 2:20 a.m. Monday morning April 15.
The Captain was under pressure to perform well for the ship's owners. It was traveling too fast, taking into account sea conditions (icebergs). He elected NOT to radio for help immediately.
Rumor has it that the lowest class of travelers were actually locked in on their appointed decks such that the better classes could get off of the ship more safely.
It later transpired that materials below the original specification had been used to cheapen and speed up constructionof the ship.
RMS Titanic did NOT run into a small piece of ice showing above the surface. It ran into an iceberg, a photo of which is included here (not the actual iceberg)