Scratch space
Scratch space may refer to any of the following:
1. In general, a scratch space is a temporary location in memory that allows something to be saved. A scratch space may be used because another memory location is full, offline, or slower. For example, the CPU (central processing unit) can use the cache as a scratch space to have operations perform faster.
2. On a hard drive, there is an area dedicated specifically to temporary storage called scratch space. This volume space is commonly used with graphic design (like Adobe Photoshop) programs as an overflow when there is insufficient RAM (random-access memory). The data on a scratch disk can be erased dynamically or periodically. The picture shows Scratch Disks set up in Adobe Photoshop found under Edit, Preferences, and Performance.
Setting up an empty partition on your primary hard drive or another drive ensures adequate scratch space.