I came across various definitions of cohomology groups (motivic, Deligne) written in the form
$$ H^n(X, \mathbb{Q}(m))$$
for some integer $m$ and an algebraic variety $X$. I am used to seeing the second item in the above notation as the ring of coefficients of the cohomology (e.g. $\mathbb{Z}$ or $\mathbb{Q}$ in singular cohomology). So I was wondering what ring $\mathbb{Q}(m)$ is. But then I have found the definition
$$ A(m) := (2\pi i)^m A \subseteq \mathbb{C}$$
for subrings $A \subseteq \mathbb{R}$. I am even more puzzled, because $A(m)$ is not a ring, only an abelian group. Can someone explain to me what is meant in general with $\mathbb{Q}(m), \mathbb{R}(m)$ and the like and whether they have anything to do with the coefficients of, for instance, singular cohomology?