This paper considers the short-and long-memory linear processes with GARCH (1,1) noises. The functional limit distributions of the partial sum and the sample autocovariances are derived when the tail index α is in (0, 2), equal to 2, and in (2, ∞), respectively. The partial sum weakly converges to a functional of α-stable process when α < 2 and converges to a functional of Brownian motion when α ≥ 2. When the process is of short-memory and α < 4, the autocovariances converge to functionals of α/2-stable processes; and if α ≥ 4, they converge to functionals of Brownian motions. In contrast, when the process is of long-memory, depending on α and β (the parameter that characterizes the long-memory), the autocovariances converge to either (i) functionals of α/2-stable processes; (ii) Rosenblatt processes (indexed by β, 1/2 < β < 3/4); or (iii) functionals of Brownian motions. The rates of convergence in these limits depend on both the tail index α and whether or not the linear process is short-or long-memory. Our weak convergence is established on the space of càdlàg functions on [0, 1] with either (i) the J 1 or the M 1 topology (Skorokhod, 1956); or (ii) the weaker form S topology (Jakubowski, 1997). Some statistical applications are also discussed.