Alignment means arranging into a line or adopting a non-random, predictable position with respect to a certain cue or signal. Sun basking, attentive listening, turning away from blending light or whipping wind, curious gazing on object of interest are associated with alignment. Alignment is advantageous: It helps to acquire information, reduce noise, avoid overstimulation, or to save energy. Study of alignment has a heuristic potential: It informs about motivation and sensory capacity of an animal. The hierarchy of senses, motivation, and actual requirement determine which kind of alignment may prevail (and mask other possible kinds of alignment). Magnetic alignment (= alignment with respect to magnetic field lines) is one type of sensory alignment with all the attributes mentioned above. For many animals the magnetic sense is an ordinary sense guided by similar principles as other senses. The selection pressure on the magnetic sense may be lower than in the case of most other senses. Accordingly, individual variability in its efficacy may be larger than in the case of other senses (cf. color blindness, tone deafness, or different types of anosmia in humans). Even in the context of spatial orientation it may be inferior to other senses. We point out misunderstandings of the concept of magnetic alignment and caveats of its study in the lab and in the field. We present examples of mammals displaying magnetic alignment in different behavioral contexts and discuss its putative meaning in the context of cognitive mapping, crossmodal integration, directional or slope indicator, and distance measuring.