There are a lot of algorithms at our disposal for supervised learning. We choose the algorithm based on the task and the data we have at our disposal. If we don't have much data and there is already some knowledge around our problem, deep learning is probably not the best approach to start with. We should rather try simpler algorithms and come up with relevant features based on the knowledge we have.
Starting simple is always a good practice; for example, for categorization, a good starting point can be a decision tree. A simple decision tree algorithm that is difficult to overfit is random forest. It also gives good results out of the box. For regression problems, linear regression is still very popular, especially in domains, where it's necessary to justify the decision taken. For other problems, such as recommender systems, a good starting...