This document discusses Spark ML pipelines for machine learning workflows. It begins with an introduction to Spark MLlib and the various algorithms it supports. It then discusses how ML workflows can be complex, involving multiple data sources, feature transformations, and models. Spark ML pipelines allow specifying the entire workflow as a single pipeline object. This simplifies debugging, re-running on new data, and parameter tuning. The document provides an example text classification pipeline and demonstrates how data is transformed through each step via DataFrames. It concludes by discussing upcoming improvements to Spark ML pipelines.