I found this in a cross validated forum and trying to understand the math notation here.

A standard linear model (e.g., a simple regression model) can be thought of as having two ‘parts’. These are called the structural component and the random component. For example:

Y=β0+β1X+εwhere ε∼N(0,σ2)

Y=β0+β1X+εwhere ε∼N(0,σ2)

The first two terms (that is, β0+β1Xβ0+β1X) constitute the structural component, and the εε (which indicates a normally distributed error term) is the random component.

I am not sure what the notation represented by the big “N” is called. I looked in rapidtables but did not see this notation there.