What is an iOS configuration profile?

Configuration profiles are XML files which can be found on iOS devices under Settings -> General -> Profile. Each profile includes custom settings, which are normally distributed by companies or organizations to a large number of devices. Settings which can be defined by these configuration files include the following:

CalDAV calendar service settings
Credentials and keys
Email server settings
Exchange settings
LDAP directory service settings
Restrictions on device features
VPN settings
Web clips
Wi-Fi settings

Profiles can be installed in various ways, using an email message, web page, or the iPhone Configuration Utility software. If a particular profile is causing issues or the settings are no longer relevant, the profile can easily be deleted.