Why do you think these sources are called "secondary"?

These sources are called "secondary" because they are created by individuals or organizations who did not directly witness or participate in the events or phenomena they are discussing. Instead, secondary sources analyze, interpret, or comment on primary sources or primary information obtained from firsthand sources. They offer a second-hand account of the information by presenting the opinions, interpretations, or analyses of primary sources. As a result, secondary sources provide added perspective and analysis to the original data or events and serve as a valuable reference for researchers and readers.

make it short

Secondary sources are called so because they analyze, interpret, or comment on primary sources without directly witnessing or participating in the events. They provide added perspective and analysis to the original information.