Historical Primary Sources
Primary Sources at Johns Hopkins
Keywords are the central concepts or ideas that you are searching for--they could be people (Calico Jack, pirates), places (the south sea, Bermuda), or things (the jolly roger, astrolabes). But, they may also be concepts or ideas (egalitarianism, mercantilism).
One of the things to be aware of in keyword searching for primary sources is that your keywords need to match those in the primary sources in order to find the best results. Sometimes that may be a matter of finding the comparable term for the period you are interested in. Almost always, it means you should consider a list of synonyms for your keywords (pirate, buccaneer, sea rover, privateer). But, with primary sources, especially those from the 18th century or earlier, it also means contending with variation in spelling.
A researcher interested in hurricanes in the early Carribbean would need to not only use "hurricane" as a keyword but consider synonyms like whirlwind, tempest, storm, and squall. Furthermore, they would need to search for hurricane, huracan, furcanes, hurry-cano, or hurricano. Likewise, for whirlwind, they might need to search for whirlewind.
Accounting for variation in words and spelling from the start will help you find the sources you need. The tips below can help facilitate the process once you have identified your keywords and search terms.