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We classify condensed matter systems in terms of the spacetime symmetriesthey spontaneously break. In particular, we characterize condensed matteritself as any state in a Poincar\'e-invariant theory that spontaneously breaksLorentz boosts while preserving at large distances some form of spatialtranslations, time-translations, and possibly spatial rotations. Surprisingly,the simplest, most minimal system achieving this symmetry breakingpattern---the "framid"---does not seem to be realized in Nature. Instead,Nature usually adopts a more cumbersome strategy: that of introducing internaltranslational symmetries---and possibly rotational ones---and of spontaneouslybreaking them along with their space-time counterparts, while preservingunbroken diagonal subgroups. This symmetry breaking pattern describes theinfrared dynamics of ordinary solids, fluids, superfluids, and---if theyexist---supersolids. A third, "extra-ordinary", possibility involves replacingthese internal symmetries with other symmetries that do not commute with thePoincar\'e group, for instance the galileon symmetry, supersymmetry or gaugesymmetries. Among these options, we pick the systems based on the galileonsymmetry, the "galileids", for a more detailed study. Despite some similarity,all different patterns produce truly distinct physical systems with differentobservable properties. For instance, the low-energy $2\to 2$ scatteringamplitudes for the Goldstone excitations in the cases of framids, solids andgalileids scale respectively as $E^2$, $E^4$, and $E^6$. Similarly the energymomentum tensor in the ground state is "trivial" for framids ($\rho +p=0$),normal for solids ($\rho+p>0$) and even inhomogenous for galileids.

Zoology of condensed matter: Framids, ordinary stuff, extra-ordinary stuff