The service is referred to by different colloquialisms depending on the region.
It’s called giving him a taste of his own medicine…
Text messages can also be used to interact with automated systems, for example, to order products or services from e-commerce websites, or to participate in online contests.
Advertisers and service providers use direct text marketing to send messages to mobile users about promotions, payment due dates, and other notifications instead of using postal mail, email, or voicemail.
The difference between acronyms and shorthand is that with acronyms, (for example, 'ESP' is an initialism for 'extra sensory perception' whereas 'esp. The online practice is to refer to shorthand, initialisms, or abbreviations as acronyms.
The majority of the expressions you see above are not acronyms, but rather shorthand used while text messaging or IMing.