Adobe Acrobat Reader is free, and freely distributable software that lets you view and print Portable Document Format (PDF) files.

Acrobat Reader also lets you fill in and submit PDF forms online.

Adobe Portable Document Format
Invented by Adobe Systems and perfected over 15 years, Adobe Portable Document Format (PDF) lets you capture and view robust information - from any application, on any computer system - and share it with anyone around the world.

Adobe Reader 9 software adds much new functionality, especially relating to collaboration, PDF file creation, security, and an enhanced user experience.

Improved launch speeds
Looking for faster launch speeds? Adobe has enhanced general performance and, in particular, has reduced launch times with Adobe Reader 9. Try it: You'll notice the difference.

PDF Portfolios
Packages, introduced in Adobe Reader 8, have been greatly enhanced and renamed. Portfolios provide easy navigation when you work with multiple PDF documents and other document types. They also enable you to work with a collection of materials such as drawings, e-mail messages, spreadsheets, and videos as a single file, which makes distribution, storage, retrieval, and collaboration easy for end users.

Native Adobe Flash support
Adobe Reader 9 can natively display rich media content, which you'll notice immediately with Portfolios. Interested in viewing SWF and FLV files? Adobe Reader 9 is the answer.

Acrobat.com (beta)
Included with Adobe Reader 9 is Acrobat.com (beta), an exciting new set of online services from Adobe. With Acrobat.com, you can create PDF files online; create and coauthor documents with others; host live web meetings; upload and share PDF files and other types of documents and control who has access to them; and even embed a rich, interactive preview of your document in a web page.

All of these services and more are provided online, so you can access them from anywhere. And you'll find easy access points from within Reader 9. As an added convenience, Acrobat.com leverages Adobe AIR, so you can interact with Acrobat.com from your desktop. Acrobat.com on Adobe AIR is a small application that is included with your download of Adobe Reader 9. Available in select languages.

Improved CAD and geospatial functionality CAD and geospatial functionality have been greatly enhanced in Adobe Reader 9. For instance, CAD designs or geospatial maps that have been converted to PDF offer Adobe Reader users access to CAD features, such as dimensions, or map features, such as longitude and latitude, for powerful collaboration and interaction.

PDF Standards Pane
When a PDF/A or PDF/X standard compliant file is opened, a Standards Pane appears and provides important file details.

Security enhancements
Adobe Reader 9 provides new digital signature functionality for an improved user experience. The new version also adds support for 256-bit AES encryption.

Accessibility enhancements
Adobe Reader 9 significantly improves the viewing of XFA forms for accessibility, while providing greater screen reader support.

Adobe Reader 9 MUI
Adobe Reader 9 MUI is Adobe's Multilingual User Interface version. This product is capable of installing any combination of supported languages. So, for example, you can install French, German, and Spanish simultaneously and then have the capability to switch among those languages within Adobe Reader. The user interface changes to the appropriate language on the fly.

Here are some key features of "Adobe Reader":

Enhance interaction with PDF Portfolios:
- PDF Portfolios provide easier navigation when you work with multiple PDF documents and other document types. Portfolios also enable you to work with a collection of materials such as drawings, e-mail messages, spreadsheets, and videos as a single file, which makes distribution, storage, retrieval, and collaboration easy for end users.

Work with Acrobat.com (beta):
From Reader 9, you can go directly into Acrobat.com (beta), an exciting new set of online services from Adobe, to perform common tasks, such as:

Create up to five Adobe PDF files:
- Share and store documents on the web
- Create and collaborate on a document in Adobe Buzzword
- Easily share your screen using Adobe ConnectNow
- You can also help colleagues, clients, and partners get on the same page at the same time with the ability to conavigate documents. Simply use Acrobat.com services to enable collaboration on a PDF file, and then distribute the PDF file and walk recipients through it in real time by controlling their page view.

- As an added convenience, Acrobat.com leverages Adobe AIR, so you can interact with Acrobat.com from your desktop as well. Acrobat.com on Adobe AIR is a small application that is included with your download of Adobe Reader 9.

Interact directly with Adobe Flash software:
- Adobe Reader can natively display rich media content, enabling a new level of end-user interaction.

Realize more secure document workflows:
- Better protect documents, forms, and drawings by leveraging Adobe LiveCycle ES and Adobe Acrobat software. Whether you want digital signatures for authenticity and integrity or document rights management for confidentiality, authorization, and accountability, Adobe Reader is the perfect solution.

Get more done with a simplified user interface:
- View information more precisely and efficiently with the Adobe Reader user interface. Choose the reading mode to fit more content on the screen or the two-up mode to view page spreads without excess space in the middle. Zoom in, pan over, or leverage the loupe feature to take a closer look.

Search single or multiple PDF files:
- Find and retrieve any PDF document or a phrase within a document in a matter of seconds. Search for words in page content, annotations, bookmarks, form fields, or document metadata within any PDF file on a local computer.

Complete forms online as well as offline:
- Enable customers to confidently act on information — filling, saving, and electronically submitting forms.

Leverage CAD and geospatial functionality:
- CAD designs or geospatial maps that have been converted to PDF offer Adobe Reader users access to CAD features, such as dimensions, or map features, such as longitude and latitude, for powerful collaboration and interaction.
- Additional features for IT managers, architects, and developers
- Enable Multilingual User Interface
- Adobe Reader MUI is Adobe's Multilingual User Interface version. This product is capable of installing any combination of supported languages. So, for example, you can install French, German, and Spanish simultaneously, and then have the capability to switch among those languages within Adobe Reader. The user interface changes to the appropriate language on the fly.

Deploy Adobe Reader using industry-standard tools:
- Quickly manage and control Reader deployments using the Adobe Customization Wizard, IBM Tivoli, Microsoft Systems Management Server, Windows Group Policy Objects, or Active Directory. Centrally host Reader using Citrix Metaframe Presentation Server or Microsoft Windows Terminal Server.

Support extended teams across operating systems:
- Deliver a reliable experience across operating systems. Reader supports a wide variety of operating systems, including Microsoft, Macintosh, Linux, and Solaris.

Enjoy support for security standards:
- Reader supports leading security standards, including SOAP/WSDL, XSD, Kerberos, W3C XML digital signatures, 256-bit AES, OASIS WS-Security, HTTP/HTTPS, RSA, XML encryption, and ECMAScript for XML (E4X) in the JavaScript interpreter. Reader is also NIST PKI test-suite compliant.

Develop new capabilities:
- Extend the functionality of Adobe Reader using the Acrobat software development kit (SDK), now available free of charge.

Leverage accessibility features:
- Reader helps meet the accessibility requirements mandated by Section 508 of the amended U.S. Rehabilitation Act. Try the Read Out Loud capabilities, or change the reading order of pages or columns after PDF files are tagged to accommodate preferences.

Support international standards:
- Reader supports the new ISO Standard 32000 for PDF. Also, Reader continues to support PDF/A, the ISO-approved standard for the long-term preservation of electronic documents; PDF/X (printing); PDF/H; PDF/E (engineering); XMP/RDF; and ODBC.

Requirements:

- Intel Pentium III or equivalent processor
- 128MB of RAM (256MB recommended for complex forms or large documents)
- 110MB of available hard-disk space
- Microsoft Internet Explorer 6.0 or 7.0, Firefox 1.5 or 2.0, Mozilla 1.7, AOL 9