近年来，机器学习在物理中有广泛应用。本文系统地介绍了机器学习方法，对进一步应用机器学习解决科学研究中的实际问题有较大帮助。通常完整的机器学习算法包括模型，数据集，优化算法，正则化过程等部分。本文对机器学习结构进行了详细总结，包括训练集、验证集和测试集的作用，代价函数形式，梯度下降等常用的优化算法以及正则化方法。此外，本文还介绍了目前广泛应用的几种深度学习网络。

In recent years, machine learning is widely used in physics. Machine learning methods are introduced systematically in this paper, which is helpful for further application of machine learning in scientific research. Generally, a complete machine learning algorithm includes a dataset, an optimization algorithm, regularization process and a model. This paper summarizes machine learning methods and several common deep neural networks.