how radar works in the ocean

I've always been curious to this, and have never been able to figure out how radar systems detect ships in the ocean. I understand how radar works in the sky, but for some reason I cannot grasp how it works in an ocean setting. I understand ping, with it being sonar, but outside of that, how do they get ships to pop up on radar?
Radar systems work by sending out a focused pulse of microwave energy at an object, most likely a cloud [1]. Part of this beam of energy bounces back and is measured by the radar, providing information about the object [1]. Marine radar works similarly, but with radio waves instead of microwave energy [4]. When the radio signal hits an object, it gets reflected back to the radar, which can then calculate a rough estimate of the object [4]. Radar is used to detect objects and their position relative to your current location [4]. It does so by detecting other ships and land obstacles, to give bearing and distance for collision avoidance and navigation while on water [4].
Marine radar, or Radio Detection and Ranging, works by sending out a radio signal that hits an object and gets reflected back to the radar, allowing it to make a rough estimate of the object's bearing and distance [1]. Marine radars use X band or S band radars on ships and are an electronic navigation instrument that uses a rotating antenna to sweep a narrow beam of microwaves around the water surface surrounding the ship to the horizon, detecting targets by microwaves reflected from them, generating a picture of the ship's surroundings on a display [1, 2]. Radars are rarely used alone in a marine setting; rather, they are typically integrated into a full suite of marine instruments including chartplotters, sonar, two-way marine radio, satellite navigation receivers such as the US Global Positioning System (GPS), and emergency locators (SART) [3]. Marine radar systems are vital navigation components for safety at sea and near the shore [3].