On the left side, how does Facebook order your friends?

[My name is...]

One friend in particular keeps showing near the top, though I don't interact with him much on Facebook. Some of the friends are the same. But I don't interact with them or click on their profiles either. Is it how often they look at my posts?

[Rom Cartridge]

According to Facebook:

“Friends who you publicly interact with the most appear first on your profile. Examples of public interactions include Wall posts, comments and mutually attended events — Facebook will never show friends based on whose profiles you choose to view or who you interact with over messages and chat.”