Observational cosmological probes of the matter power spectrum and the wavenumber (k), scale factor (a), and redshift (z) ranges to which they are approximately sensitive. From early to late Universe: cosmic microwave background (CMB, purple), CMB lensing (ΦΦ, light blue), the Lyman-alpha forest (Ly α, orange), quasi-stellar objects (QSOs, red), galaxy clustering (gg, green), cosmic shear (γγ, dark blue), and cluster abundance (CA, white). The black curve separates the linear and nonlinear collapse regimes. Constraining the matter power spectrum from different probes allows the localization of discrepancies in the two-dimensional (k, a) plane and provides insight into the physical origin of tensions between the measurements of different probes.