The first step in PSD to WordPress process is slicing
. Slicing means to cut and divide an image design file into multiple design files each having the different design component of the overall design. This is important because the whole design is not coded in a single image. In a website, multiple images are sewn together seamlessly, in which each component and feature has its own functionality and use.
The slicing is usually done in image editing software and most designers usually prefer Adobe Photoshop or comparable. But in the end the point is to cut the pixel perfect images and this can be performed using any image editing software including Microsoft paint. But, Adobe Photoshop only makes the job easier to perform and easier to organize.
Now, most designers make a design using a graphic software that allows layered image creation, again like Photoshop, and create design files that are already divided into different components in its layers. This effectively makes the process of slicing obsolete but still it is important to know how to do it.
Another thing to note here is that even though some features like buttons and embedded images have to cut in entirety as they cannot be created dynamically, other features like solid color background, header and footer color, or solid design features, that can be created dynamically, are not required to be cut in full. It is up to the designer and coder what they want to create dynamically and what not.