PPI

Definition:

Pixels per inch or PPI is a measure of the number of pixels displayed in an image. A digital image is composed of samples that your screen displays in pixels. The PPI is the display resolution not the image resolution.

Adobe Photoshop uses PPI and Corel Photo-Paint uses DPI for image resolution so it's no wonder everyone is confused. PPI is a function of your monitor.

DPI (dots per inch) is often used as a catch-all term for all types of resolution, including PPI, but there are specific terms depending on how the image is used.

Learn More About PPI and Resolution

"As it is used in desktop publishing, resolution refers to the dots of ink or electronic pixels that make up a picture whether it is printed on paper or displayed on-screen. The term DPI (dots per inch) is probably a familiar term if you've bought or used a printer, a scanner, or a digital camera. DPI is one measure of resolution." — The DPI Dilemma

"One of the most confusing aspects of desktop publishing is resolution and the measurement of resolution: SPI, PPI, DPI, and LPI. Often DPI is used in place of SPI and PPI although they aren't really the same." — Measuring Resolution Inch by Inch

"PPI is a function of your monitor. A pixel or "picture element" is a specific x,y coordinate (dot) on your screen. A high-resolution setting displays more pixels per inch. In practical terms, the same picture on a low resolution monitor looks larger than it does on a higher resolution monitor because the pixels are spread out over a larger area." — PPI - Display Resolution

Also Known As: display resolution | screen resolution