It’s a familiar scenario to anyone who’s spent time writing a college paper, updating a resume or bringing work home for the weekend: you plug in a USB memory stick to open a document and get to work only to get an error message staring back at you. When you’re looking down the barrel of a deadline, file format problems are enough to give any sane person an ulcer. With a basic understanding of common office file formats, you’ll be equipped to avoid a fistfight with your computer monitor next time you run up against an unfamiliar file extension.

A lot of the difficulty programs encounter reading documents saved with a different program can be attributed to the proprietary code used by Microsoft, Corel, or other big software companies. In order to protect their intellectual property, software developers encrypt the code that their programs are based on—competing programs have an economic interest in spreading their file type and not supporting their competitors’ file types. We’ve compiled a list of common file types you’re likely to encounter using home office software and included the names of the programs you’ll need to use them.

The Document

When it comes to word processors, it’s a bit baffling that so many programs can’t read each other’s simple text. They are just letters of the alphabet after all, right? Any five year old can read the alphabet, so why can’t my computer? These are common document file types along with the programs that can read them:

DOC, Microsoft Document: used by Microsoft Word 2003. By far the most common and widely used document type, any word processor should be able to read a DOC.

DOCX, Microsoft Document 2007: similar to the DOC, but uses updated coding to accommodate new features included in Microsoft Word 2007. Microsoft Word 2007 and Corel WordPerfect will have no problem with DOCX.

TXT, text file: plain text file easily read by any word processor.

RTF, Rich Text Format: originally developed to preserve formatting such as indentations, spacing, italics, etc. Works with all word processors.

PDF, Portable Document Format: Adobe created the PDF as an image based alternative to other document types. To read a PDF, you need to download the Adobe PDF Reader—it’s free online.

ODT, OpenDocument Text: Document that requires the open source and free office suite, OpenOffice.

WPD, WordPerfect Document: Corel’s standard document type. Requires Corel WordPerfect.

The Spreadsheet

Thankfully, spreadsheet formats aren’t nearly as varied as document file extensions. It’s easier to understand why a spreadsheet can be hard for third-party programs to read—they carry not only alphanumeric information, but also equations and operations. Common spreadsheet file types and associated programs:

XLS, Excel Spreadsheet: although XLS was developed as the proprietary format of Microsoft Excel, it is now usable on virtually all spreadsheet editors.

XLSX: Excel Spreadsheet 2007: Microsoft changed to the 2007 Excel format. Microsoft Excel, OpenOffice Calc, and Corel Quattro can read the XLSX file type.

ODS: OpenDocument Spreadsheet
: OpenOffice’s spreadsheet format. ODS file types require a copy of the open source office program OpenOffice.

It’s always possible to encounter a totally alien file type that your word processor or office software doesn’t recognize. In this scenario, a simple internet search will tell you what program the file type belongs to. If you receive a file type that is unfamiliar in your email, don’t try to open it—you never know when someone might be trying to pass along a virus.

Be sure to read our in-depth reviews of leading home office software suites—you’ll find detailed information on word processors, spreadsheets along with rankings on how well they deal with different file types.

At TopTenREVIEWS We Do the Research So You Don’t Have To.™

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