How is PPI different from DPI?

Question

Seal

Is DPI an older term than PPI?
Do I understand correctly that now the print industry works with 300 PPI and not with 300 DPI?
Please enlighten the ignoramus.

Answer 1

Pixel Per Inch is the number of pixels per unit length (resolution) in an image that is made up of pixels or on a device (screen) that uses pixels (square-sized rectangular dots arranged in a grid that occupy each grid cell) to display an image.
Dots Per Inch - the possible number of dots per unit length (resolution) in an image (usually printed), where a dot is used to form the image.