Photoshop is a bitmap based program. Bitmap files are also known as rasterized or rastered files. Below is a brief explaination of photoshops basic tools.
Magic wand: Selects pixels by clicking on a pixel and adds similar neighboring pixels. Uses a tolerance setting in the option menu to increase or decrease the range of pixels selected.
Background color: Lower right chip in color pallet and tool pallet. Color is choosen by double clicking to bring up color picker or by clicking on a swatch or by using the eye dropper.
Type tool: Click to type, options pallet controls font type, size, format, etc. Maybe used on path created by the pen tool. Creates new layer for each new click. Type maybe rasterized to convert into pixel, can not be edited afterwards.
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