Changing

after activating event handler from the code

Hi everyone. I am new to ASP.NET technology. I am very familiar with .NET controls because I am developing for desktop, WP8 and RT. My question is: How can I change some paragraph in the HTML after user clicks on .NET Button control?
button1.Click += (sender, e) => { //here should be activated the changing of some paragraph in the HTML on the same page } I can't find connectiong between C# and HTML. This is because I am new one to ASP.NET.
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