GITBOOK-359: added Schema and Policy definition

Author: prernaadev01

docs/guardian/standard-registry/policies/README.md

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 # 🛠 Policies
 
+The process to create credit or offset claims can be validated and verified to be turned into a product that is called measurement, reporting, and verification data, also known as MRV data. Today, this process of collecting the supporting data for these carbon credits or offsets is heavily manual and prone to errors due to poor data quality, a lack of assurance, potential double counting, greenwashing, and an overall lack of trust. This is where Guardian, which leverages a Policy Workflow Engine, ameliorates the issue with the current processes. The dynamic Policy Workflow Engine can mirror the standards and business requirements of regulatory bodies. 
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+A Policy Workflow Engine is a software application that manages business processes based on business rules and business data which are defined within the context of a specific policy. A policy workflow engine, therefore, manages and monitors the state of required policy actions and the required information flow in a policy grouped into a policy workflow, and determines which are the next policy actions based on the state of a policy workflow. The policy actions may be anything from saving an application form in a document management system to sending a reminder e-mail to users or escalating overdue items to management. Policy Workflow Blocks enable different business logic to exist within the Guardian’s policy workflow engine.

docs/guardian/standard-registry/schemas/README.md

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 # 🛠 Schemas
 
+From an ESG perspective, schemas contain environmentally-oriented vocabularies of terms for representing machine- and human-comprehensible structured data. In other words, they are linguistic “templates”, “frames”, or “patterns” together with rules for using them to specify a potentially infinite multitude of numbers, phrases, sentences, or arguments, which represent environmental data. 
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+In Guardian, various environmental data produced in the course of executing policy workflows are packaged into JSON documents such as verifiable credentials and verifiable presentations. Schemas define the structure and content of these verifiable documents, enabling their automatic processing and provenance verification. It’s critical that all data required to be presented and or collected during a policy workflow has a well-defined verifiable credential schema. The schema will be used in the structural conformance verification of a document within a policy workflow.