An overview of the most common Service Cloud objects and their relationships
Account, Account Contact Relation, Case, Case Article, Case Comment, Case History, Case Milestone, Case Related Issue, Case Solution, Case Team Member, Case Team Role, Category Data, Category Node, Contact, Contact Request, Contract Line Item, Email Message, Entitlement, Entitlement Contact, Incident, Knowledge Article, Knowledge Article Version, Milestone, Problem, Service Contract, Solution, Swarm, Swarm Member
See Salesforce Data Model Notation.