Need to be enlighten with this

Thanks for reading this thread I just downloaded the plugin Worktime and
I want to add some features. Here is the flow:

If the user clicked the WorkTime menu, the worktime will be displayed
and there will be a button that if you click it, it will then proceed to
another page.

here is my code in the controller:

def showall
  @eskietest = "test"

In my view:

<%= @eskietest%>

So I expect that it will display "test" message but there is no display
If I will change the code from <%= @eskietest%> to <%= :eskietest%>
then the "test" message will appear. Please explain to me why. Thanks