Why do some attributes start with '@' while others done't?

[rsw0x via Digitalmars-d]

On Friday, 22 January 2016 at 15:34:18 UTC, Wyatt wrote:
> On Friday, 22 January 2016 at 08:23:48 UTC, Ola Fosheim Grøstad 
> wrote:
>>[...]
> "Contemporary". ;)  Aside from Swift's optional semicolons, 
> they're really not all that different.
>
>> [...]
>
> Like Swift, C#, Javascript, Go, Haxe, Rust, Dart, et al?  
> Really, people have been predicting the death of curly-braces 
> languages for decades now, and they're as strong as ever.
>
> Do you have anything to base this on, or is it just what you'd 
> (apparently) like to see?
>
> -Wyatt

Maybe it's just me, but without my comfy braces I get lost. Large 
python files feel like a maze to me honestly.
Lispers might have been onto something.