Just briefly, why are the following three lines not identical in their impact?

```
if @controller.controller_name == "projects" || @controller.controller_name == "parts"

if @controller.controller_name == ("projects" || "parts")

if @controller.controller_name == "projects" || "parts"

```

The first gives me the result I want, but as there's actually more options than just projects and parts, using that form creates a verbose statement. The other two are more compact, but don't give me the same result.