Chapter 15, “Summary of changes,” summarizesin tabular format the changes to Abaqus elements, keyword options, user subroutines, and output variableidentifiers. Chapter 14, “User subroutines, utilities, and plugins”: additional user programs that can be run withAbaqus.Each entry in these chapters clearly indicates the Abaqus product or products to which the feature appliesand includes crossreferences to more detailed information.Chapter 13, “Output and visualization”: obtaining, postprocessing, and visualizing results from Abaqusanalyses.Chapter 12, “Execution”: commands and utilities for running any of the Abaqus products.Chapter 11, “Meshing”: features related to meshing your model.Chapter 10, “Interactions”: features related to contact and interaction modeling.Chapter 9, “Constraints”: kinematic constraints.Chapter 8, “Prescribed conditions”: loads, boundary conditions, and predefined fields.Chapter 7, “Elements”: new elements or changes to existing elements.Chapter 6, “Materials”: new material models or changes to existing material models.Chapter 5, “Analysis techniques”: features related to analysis techniques in Abaqus.Chapter 4, “Analysis procedures”: features related to defining an analysis.Chapter 3, “Modeling”: features related to creating your model.Chapter 2, “General enhancements”: general changes to the Abaqus interface.Chapters 2–14provide short descriptions of new Abaqus 6.13 features in AbaqusStandard, AbaqusExplicit, AbaqusCFD,and AbaqusCAE, categorized by subject: Introduction to Abaqus 6.13This document introduces features in Abaqus that have been added, enhanced, or updated since theAbaqus 6.12 release.Chapter 1 provides a brief overview of the Abaqus products included in this release.