** 1. What do we mean by a linear model and superposition? **
Students often confuse straight lines and linear models. It is important to form a clear distinction and to emphasis the concept of superposition which is a powerful model and simulation device.

Linear models and superposition.

** 2. Linearisation using Taylor series: **
Gives a brief introduction to a Taylor series and illustrates its use to linearise non-linear functions.

1st order Taylor series and linearisation.

** 3. Linearisation of models: ** This note gives a simple algorithm and then some worked examples of developing linear model approximations to nonlinear models.

Linearised modelling case studies.