ACT is Anderson's theory of the way declarative and procedural knowledge interact in complex cognitive processes. 
ACT-R is a model of information processing that integrates a network representation for declarative knowledge and a production-system representation for procedural knowledge
basic level is a degree of specificity of a concept within a conceptual hierarchy, which seems to be the degree to which most speakers describe the concept (sometimes termed a natural level); generally neither the most abstract nor the most detailed degree of specificity, but usually the degree of specificity that has the largest number of distinctive properties (i.e., properties that distinguish the given concept from other concepts at the same level of specificity)
category is a kind of concept that functions to organize other concepts based on common features or similarity to a prototype
characteristic features are the qualities that describe a prototypical model of a word (or concept) and thereby serve as the basis for the meaning of the word (or concept), according to prototype theory; these qualities will characterize many or most of the instances of the word (or concept), but not necessarily all instances
concept is an idea or a thought about something, to which various characteristics may be attached and to which various other ideas may be connected; may be used to describe either abstract or concrete ideas
converging operations are the use of multiple approaches and techniques to come together in addressing a problem or in responding to a question
core is a set of defining features of a concept, all of which are required in order for a particular example to be considered an instance of the concept; the core of defining features may be considered to complement the prototype, which comprises the characteristic features of most examples of the concept
defining features are a set of component characteristics, each of which is an essential element of a given concept, and which together compose the properties that uniquely define the concept, according to componential theory
exemplar is one of several typical representatives of a particular concept or of a class of objects; sometimes, several exemplars may be used as a set of alternatives to a single prototype for deriving the meaning of a concept
jargon is a specialized set of words, phrases, and idioms commonly developed and used within a group sharing a common purpose or a common activity
modular is occurring in distinctive units of discrete processes or areas, rather than in an integrated manner across various processes or areas
network is a web of labeled relations (e.g., category membership, attribution) between nodes
node is an element of a propositional or semantic network. 
node is element representing a concept within a semantic network; each node is linked in relationships with other nodes in the network
parallel distributed processing (PDP) is a model of knowledge representation and information processing, which proposes that knowledge is represented within a network in which information is stored in the form of various patterns of connection strengths, the patterns of connections are distributed across the brain, and information processing occurs through parallel processing of activated connections
parallel distributed processing (PDP) is a theory of neural information.
parallel processing is means by which various information processes may be executed simultaneously
parallel processing model is conceptual model of memory in which the cognitive manipulation of multiple operations occurs simultaneously; as applied to short-term memory, the items stored in short-term memory would be retrieved all at once, not one at a time (see also parallel distributed processing)
production is a condition-action ("if-then") sequence, often used in the implementation of a procedure
production system is an ordered set of productions in which execution starts at the top of a list of productions, continues until a condition is satisfied, and then returns to the top of the list to start anew
production systems are systems that represent problem-solving competencies as sets of productions. 
productions are condition-action rules that encode the situations in which it is appropriate to take a particular problem-solving operator. 
prototype theory is one of two primary theories of semantics; this theory claims that the meaning of a word (or concept) can be understood in terms of a prototype, which best represents a given word and which comprises a set of characteristic features that tend to be typical of most examples of the word
schema is a cognitive framework for meaningfully organizing various interrelated concepts, based on previous experiences
schema is a representation of members of a category in terms of what type of objects they are, what parts they tend to have, and what their typical properties are. a slot-value structure is used to represent this information. 
script is structure for a schema involving a common understanding about the characteristic actors, objects, and sequence of actions in a stereotypical situation
scripts are a schema representation proposed by Schank and Abelson for event concepts. 
serial processing is means by which only one information process is executed at any one time, and multiple processes are handled sequentially
spreading activation is process by which stimuli excite units (or nodes) within a network, and excited units cause connected units to become active
spreading activation is the proposal that activation spreads from sources to other parts of the memory network, activating the memory traces that reside there.