Understanding Data - Data Points: Visualization That Means Something - page 9

FIGURE 1-5 GPS traces collected by Aaron Parecki, http://aaronpa recki.com
This is perhaps the appeal behind the Quantified Self movement, which aims
to incorporate technology to collect data about one's own activity and habits.
Some people track their weight, what they eat and drink, and when they go
to bed; their goal is usually to live healthier and longer. Others track a wider
variety of metrics purely as a way to look in on themselves beyond what they
see in the mirror; personal data collection becomes something like a journal
for self-reflection at the end of the day.