Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons. 

This study guide on lines and angles covers key terminology; line notation; parallel, perpendicular, and skew lines; and postulates and theorems about lines. It is available for download with free registration.

This study guide on lines in a coordinate plane covers key terms, what different line slopes look like, postulates about parallel and perpendicular lines, the slope-intercept equation, how to graph parallel and perpendicular lines, and...

A list of geometry definitions and a matching activity.

A complete reference guide to points, lines, and planes. It provides definitions and interactive activities that enhance further explanation.

A complete reference guide to horizontal lines. It provides definitions, examples, and an interactive activity that enhances further explanation. Includes links to related topics.

Looks at the lines of symmetry in different types of polygons. Includes ten practice questions. Each question is accompanied by an explanation of the answer.

This study guide on Geometry covers some key vocabulary, drawing and labeling diagrams, describing geometric figures, and basic postulates for points, lines, planes, and intersections. It is available for download with free registration.

This tutorial provides an explanation and example of parallel lines.

Explains the terms and symbols used to discuss line angles, what an angle is, and the types of angles. Includes short video lesson demonstrating how to use a protractor to measure an angle. [0:57]

This encyclopedia entry from Wikipedia offers a discussion on hyperbolic geometry. The site explains how the hyperbolic geometry plane is represented in two dimensions and how lines in the plane must be drawn. Other types of models for...

[Free Registration/Login may be required to access all resource tools.] This study guide reviews the terminology for circles (tangent, arcs, central angles) and the equation for a circle.

The tutorial examines basic geometry vocabulary. Definitions and examples of a point, line, line segment, ray, and plane are included.