Small $x$ and Small $Q^2$

I discuss (i) hadron-hadron and photon-hadron total cross-sections, (ii) elastic scattering, (iii) the r^{o}le of minijets in total cross-sections and the need to include them in Monte-Carlos for small-$x$ structure functions, (iv) how the two pomerons affect small-$x$ behaviour, and (v) rapidity-gap physics.