In this project, one infinite impulse response filter and four finite impulse response (FIR) filters were researched. Each digital filter has a pair of 'Questions' and 'Solution' notebook. The reason of why I prefer this structure is to test yourself before jumping into 'Solutions'. Each notebook has intended learning objectives in the beginning of the notebook cells. Each 'Solution' notebook follows the same structure. Firstly, the theory of the relevant digital filter is explained and then practiced at the code part. Each code has an explanatory comment. The results and remarks from the codes have been explained in detail and supported by visualisations in order to be intelligible. Some insights from the signal data have been assessed creating tabular data.