The segments

Who struggles and who does not.

The part

What it is

New against experienced, device type, and entry route. A problem affecting only new users is invisible in an aggregate that is mostly experienced ones.

Segmenting the analytics before observing is what makes the observation target the right people.

The smallest level

The attributes it carries

Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.