PDF (or Portable Document Format) is used for representing two-dimensional documents in a manner independent of the application software, hardware, and operating system.
Each PDF document contains a complete description of the document, including images, text, vector graphics, raster images, and may contain the necessary fonts to display text. To view PDF documents you need to have certain computer programs, which are free and can be found via the Internet.
PDF files can be used on most platforms, Linux is also included. The free Adobe Reader is the PDF-leader and allows Linux users to read any PDF files, but we have reviewed some alternative viewers you can use to open PDF files in Linux. Here’s the list of 5 most used:
1. Adobe Reader – freeware for Linux.
2. Evince – the default PDF viewer for GNOME.
3. Xpdf for the X Window System.
4. KPDF for the K Desktop Environment.
5. Foxit Reader by Foxit Software.
The Adobe Reader (aka Acrobat Reader) is available as a no-charge download from Adobe’s web site, and allows viewing & printing any PDF files. The new Adobe Reader 9.1.3 (for Linux) doesn’t have any critical security vulnerabilities while providing more stability. The update is available as a full Adobe Reader 9.1.3 installer and can be downloaded from the Adobe FTP server. This multilingual update is available in the following language versions: English, French, German, and Japanese.
-32-bit Intel Pentium processor or equivalent
-Red Hat® Linux WS 5, SUSE® Linux Enterprise Desktop (SLED) 10 SP2 or Ubuntu 7.10
-GNOME or KDE Desktop Environment
-512MB of RAM (1GB recommended)
-150MB of available hard-disk space (additional 75MB required for all supported font packs)
-GTK+ (GIMP Toolkit) user interface library, version 2.6 or later
-Firefox 2.0 or later
-OpenLDAP and CUPS libraries
This is the most popular PDF viewer, but there are some alternative viewers and you are welcome to try them too.
Evince is a document viewer for multiple document formats as pdf, postscript, djvu, tiff and dvi. The goal of evince is to replace the multiple document viewers that exist on the GNOME Desktop with a single simple application. Evince has ben included by GNOME since GNOME 2.12 was released. It is written mainly in C and C++. It has been released under the GNU General Public License, so Evince is free software. It’s not just a PDF viewer, and it’s doing the job very well.
-Search – Integrated search displaying the number of results found and highlights the results on the page.
-Page Thumbnails – Thumbnails of pages show quick reference for where you’d like to go in a document.
-Document Printing – Using the GNOME/GTK printing framework Evince can print any document it can open.
-Encrypted Document Viewing – Evince can open PDF documents that have been encrypted.
Xpdf is an open source PDF viewer for the X Window System and runs on UNIX, VMS, and OS/2. The non-X components (pdftops, pdftotext, etc.) also run on Win32 systems. Xpdf includes programs which extract images from PDF files or convert PDF to PostScript or text, so it’s not a somple PDF viewer. These programs run on DOS, Windows, Linux and Unix.
It also has been licensed under the GNU General Public License. You can see the Xpdf web page for download links. Source code, precompiled binaries and language support packages of the current version Xpdf 3.02pl3 are available for Linux, Spartac and DOS/Win32.
KPDF is a PDF viewer, based on xpdf for KDE (K Desktop Environment). Same as original Acrobat Reader, it provides side panel with thumbnails, allows double page mode. The TTS (text-to-speech) of PDF documents is also included.
The latest version KPDF 0.5.10. was released on August 26, 2008 and has some interesting features like: three different ways of searching, put fonts used by the document on the properties dialog, support for images with alpha channel, Google-like search on thumbnails, cursor wrapping over screen for continous scrolling, save zoom setting on exit and many others.
Foxit Reader is a multilingual PDF reader created by Foxit Software. It is available as freeware but has also a full version with enhanced functionality. As a small and fast PDF viewer, Foxit Reader currently has over 50 million users all around the world. After keeping users waiting for almost two months, Foxit Reader 3.1 has been released and it introduces many fascinating new features including internet search and favorite toolbar settings.
Foxit Reader 3.1 supports internet keyword search. You can select the text and click the pop-up search icon or press and drag the mouse directly to search for the related information in Internet. It also supports customization of toolsappearing in the Favorite Toolbar area, so that users can choose the tools that are used most often easily and quickly. You are welcome to look at the official website for more features.
So you shouldn’t have any problems viewing PDF files in Linux; we have recently reviewed the possibility of viewing doc files in linux and there were no problems too. We are going to check some other popular file formats in the near future, so if you would like to see any specific formats, please, let us know. You are welcome to add comments to this article so we could know what are your areas of interest.