how to insert html code in outgoing e-mail

how to insert html code in outgoing e-mail

hi, there, i plan to use my zoho account to send e-newsletters to my company's opt-in e-mail subscribers and i would like to know how to insert html code when composing an e-mail. i tried searching in the help database, but can't seem to find any info. does anyone know how to insert html code in an outgoing e-mail via zoho? i know that in outlook i can switch between regular view and source code view, and that is how i would paste in my html code, but i couldn't see how to do that in my zoho e-mail.
 
looking forward to your reply.
 
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