If you want to resize an image and not lose any quality, you need vector graphics. Unlike bitmaps, vector images use path-based methods to save image data which is easy to scale. Here is a look at some common image types. To get one image to look great at different sizes, such as a logo, you need to know how to make vector images.
Press "P" and select the Pen tool. Choose "Paths" from the "Window" menu to reveal the Paths panel. Choose one of three options depending on the kind of paths you need. Standard creates straight lines and Bezier curves, Freeform gives you the ability to create customized lines, and Magnetic follows transitions of brightness and color.
Use pathway tools, such as Lasso, Marquee and Magic Wand, to create open and closed paths. Add as many paths as possible for best results. When you finish a path, press "Enter."
Set the tolerance level for your pathways by selecting "Make Work Path" from the top right corner of the Paths panel. Higher tolerance levels use fewer anchor points to give smoother transitions
For each new work path, double click the Path name that appears in the "Paths" panel. You can also change the name of teach path if you choose. Skipping this step means new actions with replace vector drawings with new output.
To use these paths across other programs, export them from Photoshop into Illustrator. Do this by clicking "File," "Export," "Paths to Illustrator."
One tip to keep in mind is that during path conversion, any partially transparent edges will become hard-edged transitions. You can also make a path from selections of various shapes, but it is not possible to reverse this action.
Vector images have a variety of useful traits. You can transform non-vector images in Photoshop or find some useful vector stock images.