Topic: Factor Analysis

Give a brief definition of factor analysis (two sentences at most). Find an example of an assessment instrument that has clearly delineated factors.

These are often referred to as subscales in ​‌‌‌‍‍‌‍‍‍‍‍‌‍‌‍‌‍‍‍​the literature; however, the existence of subscales should be supported statistically by factor analysis.

What is the difference between exploratory and confirmatory factor analysis? please put in citations​‌‌‌‍‍‌‍‍‍‍‍‌‍‌‍‌‍‍‍​.