Keywords allow you to tag images according to the subject matter of your photos. You can use keywords to make sense of a large library of photos without spending a lot of time and effort.
I use the Keywords List in Lightroom as the primary way to make, assign and search my keywords. The list is a flexible tool that makes it easy to make sense of your whole library, no matter how large.
The video below is the opener from the Keywords Chapter in Organizing Your Photos with Lightroom 5. It outlines the use of the keyword list and how it can grow with you. I also quickly demonstrate how you can create and rearrange your Keywords within the list.
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