You can share your presentation across different platforms by exporting it to another format, such as QuickTime, PowerPoint, and PDF. You can also send your slideshow directly to iDVD, iPhoto, iTunes, GarageBand, and YouTube.
To learn about exporting your presentation to formats that are compatible on different platforms, see:
To learn about sending a presentation directly to iDVD, iPhoto, iTunes, and GarageBand, see:
To learn about quickly sending a slideshow file through Mail or sharing it on iChat Theater, see:
To learn about keeping your presentations up to date across your computers and devices, using iCloud, see: