Matching is one area of long-term memory that involves comparing and contrasting new information to information already stored for the long term. Categorization, also called "chunking," is one kind of matching that allows you to typify and classify elements in your long-term memory. Another matching skill related to long-term memory is extrapolation, which relates to applying long-term memories to better understand new information.
Long-term memory skills are divided into three sub-categories: attention, storage and retrieval. Attention involves a conscious (or unconscious) awareness of some stimulus that can be processed into a memory. Storage is the formation and maintenance of actual long-term memories in the brain. Retrieval is the skill required for recalling a memory from the recesses of the mind.
Problem-solving is a type of critical thinking in which an individual must use available information to devise a solution or develop a strategy to a complex problem. Problem-solving may be short term (for example, figuring out what kind of tool to use for a given project) or long term (strategizing how to improve one's life within the next 10 years). The problem-solving method involved in critical thinking follows several stages: stating the problem, evaluating the desired outcome, generating potential solutions, deducing the best one and executing the plan then retroactively revising the plan as needed.
Elaboration is a kind of critical thinking in which you make reasoned judgments about something not explicitly learned. It involves using available information to infer or elaborate on conclusions based on logical connections. Elaboration is especially pertinent in higher-order activities, such as reading fiction. Within the fiction text, a subtext parallels the text and contains information that's not explicitly stated but nonetheless relevant. Reading requires individuals to make logical inferences in order to get the whole picture.