What does the least squares method choose the line of best fit to do?

1. For any candidate line, measure the vertical distance from each data point to the line. 2. Square each of those distances and add all the squares together. 3. A poor fit gives a large total and a good fit gives a small one. 4. The least squares line is the one that makes that total as small as possible. 5. No straight line can pass through every point of scattered real data, so that option is impossible. _Source: Siyavula Mathematics Grade 12 (Everything Maths, CC BY 4.0), Chapter 9: Statistics_