Email Sender?

I made an online job application on the company's webpage. I have provided my yahoo email address on the same webpage.





After I have submit the webpage. The company send an auto acknowledgement to my email address.





However the email message shows my own email address as sender. The company's email address is not shown anywhere in the message.





How can this be done?

Email Sender?
You provided your email address. Thats what they go by.