Sorry not knowing Hindi but I hope they are similar things.
Letter A and Hiragana Letter A for exmaple.

#submitting A
1.keyboard          type A 
2.input method      no input method
3.browser           display string A
4.submit            sending A to server 
5.cgi on server     recieve A from client

#submitting HIRAGANA Letter A
1.keyboard          type A     
2.input method      convert to HIRAGANA_LETTER_A "???"
3.browser           display HIRAGANA_LETTER_A "???"
4.submit            sending HIRAGANA_LETTER_A encoded with "UTF-8"
5.cgi on server     recieve "UTF-8" HIRAGANA_LETTER_A from client

"???" could be UTF-16 or some system encoding.
Maybe you are confused by lacking Hindi input method

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