WorldWide Wireless Roaming
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WorldWide Wireless Data Roaming

While Wi-Fi can be found in a large number of countries, it is usually not as widely available as it is at home.  Wi-Fi access can be found in private and public places but the Wi-Fi band of frequencies in foreign countries can include a larger or smaller number of channels, be located in different 'bands', and possibly none at all.  The US Wi-Fi bands include frequencies at 2.4 and 5 GHz, with the 2.4 GHz channels (1-12) being the most common in foreign countries.

Since most smartphones provide Wi-Fi access you can use data capabilities in foreign countries as well as Calling and Text functions with appropriate apps installed.  Keep in mind Wi-Fi connections, especially in public places, are not secure.  It is not smart to send login information and passwords over an open Internet connection.

BTW, in most parts of the world outside the US, Wi-Fi is pronounced "wee-fee".
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