My wife is being charged 20p per text message, and they are categorised on the bill as "mobile internet texts". Can someone please explain to me what this means, and why it costs? She has an unlimited texting allowance. Sorry. This is confusing to me!

What is she doing that incurs the charge, and what should she be doing instead?

Are international text messages typically treated as chargeable when you have 'unlimited texting' in your package?

[It's OK - found out that you do get charged!]