Hey JohnP, Welcome here at foopshi. I'm one of the old man here.
Interesting that you're encouraging people to use iCloud. Though it's on the debate for claiming that Apple and maybe some other party could have a look at your files transferred to iCloud. I do also think that it's not that much safe to store personal data on any cloud based storage service, without encryption.
Is an application which lets you connect any data between all your Apple devices. You can add a calendar event using your iPhone, and iCloud will automatically update the calendar on your iPad and/or Mac Book.
You can take a photo using your iPhone and have it on your iPad too within seconds! iCloud can also download a new installed application on your iPhone/iPad to any other connected device.
Apple has created iCloud for PCs too, so if you own an iPhone and not a Mac, you still can use iCloud and connect your iPhone with your PC.
You will love how it lets you use your data on every single Apple device (and PC) without the need of manual data transferring. By the first time you use iCloud you have 5GB free space for your files, if you need more there is yearly fee.