This paper considers the difference operator Aht,x approximation of the following differential operator At,xu(t,x) = -a11(t,x)utt(t,x)-a22(t,x)uxx(t,x)+σu(t,x), defined over the region R+×R with the boundary condition u(0,x) = 0,x∈R. Here, the coefficients aii(t,x),i = 1,2 are continuously differentiable and satisfy the uniform ellipticity a112(t,x)+a222(t,x)≥δ>0, and σ > 0. It investigates the structure of the fractional spaces generated by this difference operator. Moreover, the positivity of Aht,x operator in difference analogy Ho¨lder spaces is proved. [ABSTRACT FROM AUTHOR]