# Overview Saino First Voice call or messaging is an automated way to call multiple numbers to deliver a voice message via call that was prerecorded or converted from a text. Also known as Voice SMS or robocalling or Voice broadcast, it delivers voice messages to any fixed or mobile phone in the world. **2-Factor Authentication** It helps companies to deliver PINs for 2-Factor Authentication and transactional messages in a quicker way and ensures 100% delivery via retry methods. Businesses use Voice messaging to inform their customers of their latest marketing offers. It is especially effective for spreading time-sensitive messages like emergency messages, last-minute updates, to generate an opinion on a certain matter, send political campaigns etc. Voice messaging helps companies to save money because it eliminates the need for call centers to spread messages via Call. **Voice API** Saino First's Voice API is a simple REST API. For an originating Voice call, you submit a POST HTTP request with a well-structured body and in response, you get a confirmation from our system. **Testing with Postman - Use below settings** ![](/files/-MC72T5VlBGlKgZAZ32h) ![](/files/-MC72Xd8R_XX8EOeV14X) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://apidocs.saino.io/voice-api/overview.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.