When sending a text, why are some bubbles green and others blue?

[iMore Question]

when sending a text, why are some bubbles green and others blue?

when sending texts, why are messages sometimes in green and sometimes in blue

 

[kch50428]

Re: when sending a text, why are some bubbles green and others blue?

Blue indicates iMessages to another iPhone/iOS device/Mac user - Green is standard carrier based SMS text messaging.