According to <http://guides.rubyonrails.org/routing.html>:

```
HTTP Verb   Path     Action     Used for
GET /photos index    display  a list of all photos
GET /photos/new  new     return an HTML form for creating a new photo
POST    /photos create   create   a new photo
GET /photos/:id  show    display a specific photo
GET /photos/:id/edit     edit   return an HTML form for editing a photo
PATCH/PUT   /photos/:id  update update a specific photo
DELETE  /photos/:id destroy  delete a specific photo

```

How does rails know when a PATCH/PUT REST is received. I understand the get/post but PATCH/PUT I cannot figure it out. Is something being done internally, like in the input.
['https://Stackoverflow.com/questions/17572348', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/2542493/']
Read about "resource routing" in the document you referenced at the top of your post.  

Also, run `rake routes` to see how rails is currently configured to route.
In The Terminal Type:

```
$rake routes

```

and hit enter

Prefix Verb URI Pattern Controller#Action

root GET / welcome#index