University System ER diagram models a complete student enrollment platform using crow's foot notation with five core entities: ALUNO (student), CURSO (course), DISCIPLINA (discipline/subject), PROFESSOR (instructor), and MATRICULA (enrollment). Data flows from CURSO to both ALUNO and DISCIPLINA, while MATRICULA serves as an associative entity resolving the many-to-many relationship between ALUNO and DISCIPLINA, with DISCIPLINA linked to PROFESSOR. This normalized structure eliminates redundancy, enforces referential integrity through primary and foreign keys, and supports complex queries on student enrollments, course assignments, and instructor workloads. Fork this diagram to customize entity attributes, add additional relationships like prerequisites or grading scales, or export as .drawio/.svg for documentation and database implementation. The crow's foot cardinality notation (1:N, N:1) clearly communicates relationship multiplicity essential for DDL generation and schema validation.