Open ODS File

ODS file extension is used to store documents in OpenDocument Spreadsheets format. OpenDocument Spreadsheets is part of generic OpenDocument standard which defines a format to store spreadsheets, word processing documents, charts and presentations in a ZIP-compressed XML format. OpenDocument standard is frequently referred to as Open Document Format for Office Applications (ODF).

OpenDocument standard was developed and is managed by Organization for Advancement of Structured Information Standards (OASIS). This format was developed based on OpenOffice.org XML format used in OpenOffice.org and LibreOffice.

Typical ODS file will contain content.xml with actual content of the spreadsheet, styles.xml with formatting styles used by the spreadsheet and meta.xml with meta information about the spreadsheet. It also may contain Pictures directory with pictures used in the spreadsheet.

You can open ODS file and edit it using many popular spreadsheets editing software including Microsoft Excel, LibreOffice, KOffice, OpenOffice.org.

If you don’t want to install software locally to your computer you can upload your ODS file to Google Docs, OneDrive or Dropbox and edit it using online cloud spreadsheet editor. Uploading ODS file to the cloud is also an easy way to send ODS file to a mobile device.

ODS files are transferred over internet using application/vnd.oasis.opendocument.spreadsheet mime type. ODS files are typically compressed using DEFLATE algorithm and further compression won’t get any significant benefit. OTS file extension is frequently used in tandem with ODS and is used to store spreadsheet templates. ODS files could be password protected and encrypted.

Open EPUB File

EPUB file extension is used to store e-books in EPUB file format. EPUB is short for electronic publication and is a technical specification developed by International Digital Publishing Forum (IDPF). EPUB file format is quite popular and is supported by many e-book readers and e-book software.

EPUB file is a compressed folder which stores files with e-book contents and layout. In some way it is easy to compare EPUB file to a small website with e-book as a content. Actual text of the e-book is stored inside one or multiple XHTML file. XHTML files could be rendered by a web browser if needed. E-book contents is stored in OPF file (typically as a content.opf). OPF is an XML based format which stores references, font and styling information related to each chapter of the book. Also, it stores e-book identification information such as ISBN, author and language of the book.

You can open EPUB file on Windows or Linux using free and open source Calibre e-book reader. Calibre also can process EPUB files and convert them to a different e-book format. This may be required to view EPUB file on Amazon Kindle device. Even though EPUB is technically supported by Amazon Kindle, there are several limitations to how EPUB file should be structured. That is why it may be easier to convert EPUB file to a different format such as MOBI, RTF, HMTML or PDF for better Amazon Kindle experience.

To open EPUB file on a mobile platform you can use Apple Books for iOS and Aldiko for Android. Or you can also use Bluefire Reader supported both on iOS and Android operating systems.

EPUB files are save for download and don’t contain scripts. You may open EPUB files downloaded from the internet without being afraid to infect your computer.

Open PRN File

PRN file extension is used by files which contain printing instructions for a specific printer. PRN files could be produced by different applications. PRN file is generated when user selects “Print to File…” option from the printing dialog and clicks on OK button. Operating system will ask for PRN file name and will save printing instructions to the selected file name.

PRN file contains printing instructions in a language used by a printer set as a target when “Print to File…” was selected. Depending on a printer and printer driver PRN file could contain instructions in Postscript, PCL, HP/GL, ESC/P, ESC/P2, RPCS, Prescribe and many more.

If your PRN file was generated for a postscript printer then you can open it via Ghostscript or Adobe Distiller. You may have to change PRN file extension to a PS in order to be able to open PRN file. Below is an example on how to convert PRN file in postscript format to PDF:

gswin32c.exe -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=output.pdf input.prn

If PRN file was generated for a PCL printer you may use GhostPCL utility to convert it to PDF. Below is an example on how to convert PRN file in PCL format to PDF:

pcl6 -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=output.pdf input.prn

You can also open PRN file by printing it. To do this click right mouse button on PRN file in question and select “Microsoft Office Document Imaging”.

PRN files may be useful when something is not working well on a printer. In that case you may generate PRN file and send it to a customer service department of printer vendor.

PRN files are not dangerous as they only can contain printer specific instructions. It is safe to open PRN files on your computer.

Open EPS File

EPS file extension is used by files in encapsulated postscript format. Encapsulated postscript file format was designed to be embedded inside the postscript files. Still it is possible to open EPS file without having it embedded into another document.

To open EPS file and view its contents you can use free Ghostscript software. Ghostscript will execute postscript commands and rasterize contents of EPS file. You can also rasterize EPS file using GIMP, Adobe Reader or Irfan View.

If you don’t want to rasterize EPS file but edit it in vector form, you can use CorelDraw or Adobe Illustrator. Both of these applications will open EPS file in a vector format giving user full flexibility in editing its content and saving it back to EPS or exporting to other supported formats.

Files in EPS format are sent over internet using application/postscript, application/eps, application/x-eps, image/eps, image/x-eps mime types.

EPS file standard requires it to draw its contents within specific boundaries defined in %%BoundingBox line. EPS file without %%BoundingBox command considered invalid. Also, many EPS files will contain a preview picture which will be used by embedding software during image browsing process. EPS files are not supposed to be edited after being embedded. Still they support transformations such as scaling, tilting and rotating the image.

Due to the use of postscript commands EPS file is device independent and can be rendered on any device. But it requires postscript rendering engine to be installed.

EPS file must conform to Document Structuring Conventions (DSC) which is a set of comments allowing to structure postscript documents so they could be manipulated without executing postscript commands.

Technically because EPS file is a fully featured scripting language it can contain malicious code but since rendering of EPS file happens within postscript processing software it limits potential attach exposure. That’s why in general EPS files are considered to be safe for download.

Open CAJ File

CAJ file extensions is used by China Academic Journals full-text database file publishing format.

China Academic Journal Articles. It is a format similar to PDF but it was specifically created for use by China Academic Journals (CNKI organization).

Alternatively, CAJ file could be generated by Autodesk Fabrication Products. CAJ file or Archived Job File will contain a full fabrication job details including a database of all settings of the Fabrication Products. Having settings in the file are frequently required when the job is transferred to another location or to a technical support representative.

To open CAJ file from China Academic Journals you can use CAJ Viewer . CAJ Viewer is a software similar to Adobe Acrobat Reader. It can open CAJ file, render page layout, perform operations with pages such as changing pages orientation, printing the file or exporting it. China Academic Journals is the only known provider of CAJ files and their contents are typically limited to articles originated from China.

To open CAJ files generated by Autodesk Fabrication Products you can use Autodesk Revit. Besides CAJ files, MAJ and ESJ files are frequently used to export information from Autodesk Fabrication Products software to Autodesk Revit.