Some of the techniques described in this chapter may appear to overlap with Camera Raw editing, but image adjustments such as Levels and Curves still play an important role in everyday Photoshop work. It also explains how to work with photos that have never been near Camera Raw, such as images that have been supplied to the people directly as TIFFs or JPEGs. Digital photographic images are constructed of pixels and as such are resolution-dependent. Photoshop is mainly regarded as a pixel-based graphics program, but it has the capability to be a combined pixel and vector editor because it does also contain a number of vector-based features that can be used to generate things such as custom shapes and layer clipping paths. The Photoshop bicubic interpolation method has been sufficiently improved to provide the optimum resampling, especially with regard to downsampling image data. The histogram graphically represents the relative distribution of the various tones that make up a digital photograph.