Numbers 1.0 on OS X was first announced on August 7 2007, and the .numbers file contains many of the standard features of a spreadsheet with support for rows, columns, graphs, formulas and charts. The iPad version of Numbers was released in January 2010, and the most recent version of Numbers on OS X is version 3.5 released in November 2014 as part of Apple's iWork '14 update.
As with other products in the iWork suite Numbers includes a variety of layouts designed by professional illustrators and also includes support for importing documents from Microsoft's Office suite (in this case Excel spreadsheets).
The key advances in Numbers are summarised below:
First version - basic features.
Adds features to allow charts in Keynote and Pages to be automatically updated when changed in Numbers files.
Support added for OS X Lion features such as "full screen", "resume", "auto save" and "versioning".
Includes features for integration with iCloud, retina display support and dictation features.
Includes improved compatibility with Excel documents, the ability to hide and unhide rows and columns amd filters.
Launched with a new UI to match that found in Pages and Keynote, and also includes the ability to create interactive charts.
New OS X Yosemite inspired design, support for iCloud drive, and an updated Numbers file format.
A .numbers file is actually a compressed ZIP file comprised of a number of other different files combined that together make up a .numbers file. The most recent version of Numbers saves files with an "Index" directory containing Apple's proprietary IWA file format, a "Metadata" directory with .plist files and one or more jpg files for allowing quick previews. Similar to Microsoft products, the .numbers file type suffers from a lack of compatibility with other leading spreadsheet programs.
PDF is a file format developed by Adobe Systems for representing documents in a manner that is separate from the original operating system, application or hardware from where it was originally created. A PDF file can be any length, contain any number of fonts and images and is designed to enable the creation and transfer of printer-ready output.
Each PDF file encapsulates a complete description of a 2D document (and, with the advent of Acrobat 3D, embedded 3D documents) that includes the text, fonts, images and 2D vector graphics that compose the document. They do not encode information that is specific to the application software, hardware, or operating system used to create or view the document.