Organisms acquire and use sensory information to guide their behaviors. Likewise, scientists acquire and use the information contained in experimental data to understand systems of interest. In both cases, the amount of information available is limited, so using it efficiently is critical. In this talk, I will discuss two aspects of information usage. First, I explore information usage by cells, describing how we have discovered that motile E. coli cells acquire very little information but use it efficiently. Second, I examine information usage by scientists, elaborating on how faced with noisy fluorescence data from E. coli cells, we developed a method to extract relevant signals from raw data with theoretically maximal efficiency. Finally, I examine similarities between the two.