Systems Biology is a nascent field that arose from the technology driven omics measurement revolution. It goes beyond mere data analysis and focuses on the biological behaviour emerging from the dynamic interactions between system components that are organized in a hierarchical and highly connected manner. Mathematical models have been used as a conceptual framework to study such systems and their impact is maximal when there is a synergistic interplay of the models with experimental data and biological domain knowledge. The review provides an introduction to the modelling process and selectively highlights manuscripts that have strong biological impact.