You can transfer information and files between your iOS devices and computers, using iCloud or iTunes.

• iCloud stores content such as music, photos, calendars, contacts, documents, and more, and wirelessly pushes it to your other iOS devices and computers, keeping everything up to date. See iCloud below.
• iTunes syncs music, video, photos, and more, between your computer and iPhone. Changes you make on one device are copied to the other when you sync. You can also use iTunes to sync files and documents. See Sync with iTunes futher down.

You can use iCloud or iTunes, or both, depending on your needs. For example, you can use iCloud to automatically send the photos you take on iPhone to your other devices, and use iTunes to sync photo albums from your computer to iPhone.