When students are in college they have different deadlines to add/drop/swap classes. Students may formally withdraw from a class by filing a Petition to Request a W (Withdraw) Grade Notation with their college academic advisers.
The W grade petition must be filed by the end of a number of weeks of instruction, depending on each university. After the deadline, students may only withdraw from a class for documented medical or emergency reasons.
A withdrawal from a class (W) is GPA-neutral: instead of a grade, students receive a W notation on the transcript, which does not bring in grade points (or credits). The class and W remain on the schedule and transcripts, allowing students you to keep full-time status.