There are several ways to transfer files between iPad and your computer or other iOS device. If you have an app that works with iCloud on multiple devices, you can use iCloud to automatically keep the app's documents up to date across your devices. See the Getting Started section -> iCloud.

Transfer files using iTunes. Connect iPad to your computer using the included cable. In iTunes on your computer, select iPad, then click Apps. Use the File Sharing section to transfer documents between iPad and your computer. Apps that support file sharing appear in the Apps list. To delete a file, select it in the Documents list, then press the Delete key.

You can also view files received as email attachments on iPad.

Some apps may share content using AirDrop. See AirDrop, iCloud, and other ways to share.