system
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human
ELI5: How did pirates/navy track down other ships back before radar/sonar?

I wondered this while watching Pirates of the Caribbean and wondered how ships chased each other down?  It's not possible to track steps through ocean.
gpt
they really didnt. But often you knew where ships were likely to be. There are only so many ports, and the bigger a ship the bigger a port it needs to be able to dock. A pirate might wait in the shipping lanes a day or two outside of a busy port and wait for a target. Or he might wait for a ship to dock and become a sitting target in an undefended port. A third choice is to cruise near nautical choke points like between islands or outside sandbars. Large convoys of vessels also usually took predictable routes, there was a range of a few degrees which offered the fastest trip to and from Europe due to trade winds and currents, and ships tried to avoid sailing in storm and hurricane season so there tended to be a good deal of activity when it was optimal for sailing.

Once a ship was in sight it was then just a matter of who was the better seaman, or which ship was to windward, and in many cases some luck. Ships might be in sight but 20 miles away and still be in a chase.