What is short-term memory?

Short-term memory is best described as a limited capacity store that maintains information for a brief period. This concept is foundational in psychology, particularly in understanding how information is processed and retained.

Short-term memory operates under the premise that it can hold a small amount of information—typically around seven items—at any one time. This memory system allows for the temporary storage of information, which makes it essential for various cognitive tasks such as learning, problem-solving, and communication. The duration of retention in short-term memory is usually around 15 to 30 seconds unless the information is actively rehearsed or encoded into long-term memory.

This understanding of short-term memory as a distinct entity from both unlimited-capacity memory systems (like long-term memory) and memory that has been completely forgotten further clarifies its role in cognitive processing. Its capacity and duration constraints differentiate it from the other types of memory discussed in the question, providing insight into how humans manage and retrieve information over different time spans.