In this book, we introduce the fundamentals of tensor computationTensor computation and its applications in modern seismic data processingSeismic data processing. There are various tensor computationTensor computation methods from various backgrounds, with the core ones covered in this book including tensor-tensor product (t-product)Tensor-tensor product (t-product), tensor completionTensor completion, tensor deep learningTensor deep learning (TDL), and tensor dictionary learningTensor dictionary learning (TDcL). These techniques collectively enable seismic data processingSeismic data processing methods to avoid vectorization or matricization high-dimensional seismic data. Through tensor computationTensor computation, the seismic data processingSeismic data processing tasks discussed in this book can be efficiently computed in tensor form, preventing potential damage to the high-dimensional geological structuresGeological structures that may occur in classical seismic data analysis. Therefore, this tensor-based approach yields better results than traditional matrix-based processing methods.