Cutting in

Cutting in means to use a paint brush or roller to paint a straight line next to an edge where two different colors will meet. This is usually done when painting a room or a wall, where you want to paint a different color or part of the wall, but you don't want to get paint on the wrong part.

For example, if you want to paint a different color on the wall and on the ceiling, you would first use a paint brush or roller to cut in along the edge where the wall meets the ceiling. This is done by very carefully painting a straight line along the edge, painting one stroke at a time. This way, when you use a roller to paint the rest of the wall a different color, the paint won't get on the ceiling because you painted a straight line to separate the colors. Cutting in can also be used for doors, windows, or other areas where two different colors will meet.

Overall, cutting in is important because it helps you paint neatly and helps keep the different colors where they are supposed to be.