The bow is the forward part of the hull of a ship or boat, the point that is farthest forward when the vessel is underway in the usual direction. The aft end of the boat is the stern.
The prow of HMS Caroline (1914)
HMS Dreadnought, with an inverted bow
The seaworthy bow of a Severn class lifeboat in Poole
A heavily laden barge in France. Note the bluff bow and the limited freeboard.
The stern is the back or aft-most part of a ship or boat, technically defined as the area built up over the sternpost, extending upwards from the counter rail to the taffrail. The stern lies opposite
Bow (watercraft)
…of the hull of a ship or boat, the point that is farthest forward when the vessel is underway in the usual direction. The aft end of the boat is the stern. Prow may be used as a synonym for bow, or it may refer specifically to the foremost part of the bow above the waterline…
Detailed schematic of an elliptical or "fantail" stern
The flat transom stern of the cargo ship Sichem Princess Marie-Chantal
1. Keel (light peach) 2. Skeg (dark purple) 3. Deadwood (olive drab) 4. Stern post (forest green) 5. Filling chock (bright yellow) 6. Filling transoms (pale yellow-green) 7. Wing transom (turquoise) 8. Helm port (orange) 9. Counter timbers (pale violet) 10. Margin (indigo) 11. Horn timber (green) 12. Stern timbers (apricot) 13. Side-counter timbers (pale yellow) 14. Quarter-timbers (red) 15. Fashion timber (fuchsia) 16. Cant frames (blue) 17. Square body frames (uncolored)
Diagram of a rounded stern as designed by Sir Robert Seppings