A QR code generator and downloader API is a web-based application programming interface that allows users to generate and download QR codes for a given URL. The API is built using a framework such as Flask and utilizes libraries like qrcode to create the QR codes. When a user makes a GET request to the API's endpoint, they pass in a query parameter that contains the URL they want to generate a QR code for. The API then converts the URL into a QR code image, and sends the image back to the user as a response. The response is set to have headers that prompt the browser to download the image. This type of API can be useful for a variety of use cases such as creating QR codes for marketing materials, business cards, or for use in retail settings. The API allows for easy and convenient generation of QR codes without the need for a separate QR code generation tool or software. In summary, the QR code generator and downloader API is a simple yet powerful tool that enables users to create and download QR codes for a given URL with just a single GET request to the API endpoint. It is built using Python and Flask and uses qrcode library for generating QR codes, making it easy for developers to integrate into their projects.