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

[Dibyendu Majumdar via Digitalmars-d]

On Thursday, 21 January 2016 at 23:08:07 UTC, Brad Anderson wrote:
> On Thursday, 21 January 2016 at 23:05:51 UTC, Dibyendu Majumdar 
> wrote:
>> I am puzzled as to why there is @nogc on the one hand and 
>> simply nothrow on the other? Why are some attributes prefixed 
>> with '@' while others aren't?
>>
>
> For historical reasons, basically. There have been some calls 
> to make it uniform but nothing has really happened.

I see. And which approach is considered better? Personally don't 
see why the '@' prefix is necessary.

Regards