What is back-end and front-end?

Question

IT terminology

I found only a vague concept, but I didn’t fully understand what it was. (Google didn’t help)

Answer 1

Web applications and complex sites are essentially client-server architecture network software, actually consisting of two parts:

1. The client part (frontend), running in the user's browser.
   
2. The server part (backend) running on servers.
   

When you clicked the "Publish" button in the form for creating a question, the frontend javascript code checked the correctness of the form, generated a request with the data contained in it and sent it to the server, on the server the backend php code accepted this data, processed it in the necessary way, and saved it to the database and returned a response to the frontend about the success of the operation, after which the browser opened the question page for you.