Flaky tests are nondeterministic tests, they can give different results without changes to the code. This wastes time and resources. A better understanding of this field should lead to a decrease of these inconveniences. However, there is little work that makes the effort to bring this knowledge together. This is why this thesis will propose to answer these questions What are the categories of flaky tests identified? and What debugging techniques are the most appropriate for the different categories of flaky tests?