Pattern refers to a set of objects or phenomena or concepts where elements appear to be similar to one another in certain ways/aspects. Cognition refers to getting acquainted with, to come to know the act, or the process of knowing an entity. Recognition refers to the feeling that the entity in consideration has been met before; the process of knowing again. 

Pattern Recognition is referred as the study of ideas and algorithms that provide machines with the capability to put abstract objects into categories. It is concerned with the classification or description of objects in noisy or complex environments.

Six Step Methodology adapted for Pattern Recognition
1. We observe the objects.
2. We study the relationships between various objects.
3. We study the relationships between the objects and ourselves and arrive at situations.
4. We study the changes in situations and come to know about the events.
5. We study the events and thus understand the law behind the events.
6. Using the law, we can try to predict events of the future.
Example scenarios: Astrology/Palmistry, DC Machines etc.

Types of Patterns
1. Spatial Patterns: those located in space. Examples include characters in character recognition, images of ground covers in remote sensing, images of medical diagnosis etc.
2. Temporal Patterns: those distributed in time. Examples include radar signals in radar detection, speech signals in automated speech recognition, sonar signals etc.
3. Abstract Patterns: neither located in space, nor distributed in time. Examples include classification of people based on psychological tests or the language they speak, medical diagnosis based on patient history etc.

Approaches towards Pattern Recognition Problems
1. Syntactic or Grammatical or Structural Approach.
2. Statistical or Decision Theoretic or Discriminant Method.

Application Areas of Pattern Recognition
Pattern Recognition can and are being applied to various problems including automated speech recognition, fingerprint identification, optical character recognition, DNA sequence identification, medical diagnosis, life form analysis, plant defense signaling, radar detection, aerial photo interpretation, weather prediction and perhaps even sensing of life on remote planets etc.