DZone Refcardz series has 6 reference cards relating to various agile methodologies and practices. These might be useful for high-level overview and quick reference:

  • Agile Adoption: Improving Software Quality (link)
  • Agile Adoption: Reducing Cost (link)
  • Agile Adoption: Decreasing time to market (link)
  • Scrum (link)
  • Getting Started with Lean Software Development (link)
  • Getting Started with Kanban for Software Development (link)

There are also few online agile glossaries which are very comprehensive:

Visual Agile Language or Visual AGILExicon© is a collection of icons and pictures that represents most of the Agile/Scrum concepts and activities. Each of these images explains the relevant concept or activity in great clarity. This collection is a great resource for preparing training and process related presentations for both new and experienced teams. Visual AGILExicon© is developed by Kenny Rubin from Innolution. The license to use this collection can be obtained at no cost from Innolution site for using in training and forum presentations. As part of the license agreement, it’s a requirement to include one slide in the presentation that provides appropriate attribution. The collection can be browsed from here.