Hello? ysangstar. Thank you for your good evaluation. The lectures I prepared are PC-based and mobile app-based, so the microphone recognition part is different from the web. If you simply want to receive voice from the web, you can do it with html5's getUserMedia, and if you are considering voice recognition, you can test it by replacing it with web speech API, etc. I understand that you have to use the https protocol. I understand that Google Cloud's speech to text shows good performance as a paid version. Thank you.