I think it'll be useful to add an example about how to visualize the results of GridSearchCV, when there're two hyperparameters. SVC will be a good choice here.
Example from Andreas's book:
https://nbviewer.jupyter.org/github/amueller/introduction_to_ml_with_python/blob/master/05-model-evaluation-and-improvement.ipynb

Also see the official guide of libsvm (P7)
https://www.csie.ntu.edu.tw/~cjlin/papers/guide/guide.pdf