How can I distinguish that my website is hit by which Update?
 

I want to know how 1 can distinguish that the website is hit by which update, either the site is hit by manual update or Algorithm update and if it is by algorithm update, then which algorithmic update has hit it.

If you hit by manual update it will shown in google webmaster tools in "manual action" field, if it is algorithm update you have audit your site completely then only you can distinguish which algorithm update hit you.

Yes, @wrightandru said correct. If your website hit by google updates manually then you got message in your google webmaster account.