# Technical terms

### Hypertext Transfer Protocol (HTTP)

Hypertext Transfer Protocol (HTTP) is an application-layer protocol for transmitting hypermedia documents, such as HTML.

### SSH File Transfer Protocol (SFTP)

In computing, the SSH File Transfer Protocol is a network protocol that provides file access, file transfer, and file management over any reliable data stream.

### RESTful API

REST APIs (which are a type of web API) involve requests and responses, not too unlike visiting a web page. You make a request to a resource stored on a server, and the server responds with the requested information. The protocol used to transport the data is HTTP. “REST” stands for Representational State Transfer.

![REST APIs involve requests and responses over HTTP protocol](https://3942185270-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MK92LXbOtBAGgXDkaxF%2F-MKjDa4jvLiRUCMS1LmP%2F-MKjWHGRXbKlKAcxpGPV%2FBeige%20and%20Gray%20Minimalist%20Quote%20Instagram%20Post%20\(1\).png?alt=media\&token=43e0caf3-40f7-4e4a-ba03-b515be154421)

### Unstructured Supplementary Service Data (USSD)

USSDs, similar to Short Message Services (SMS's), is a communication protocol that is used to send text messages. USSDs create a real-time connection during a USSD session which allows for a two-way exchange of a sequence of data. It is often used to authorise a user or to perform an action that requires the user's consent.

### Submission File

In a Host to Host (H2H) batch file integration process, submission files initiate new instructions to add new or modify existing records.

### Reply File

In a H2H batch file integration process, reply files confirm the acceptance of the submission file transmitted and include any validation failures.

### Output File

In a H2H batch file integration process, output files provide the results of the instructions provided in the submission file and as accepted in the reply file.