<Li> Structured analysis and design technique (SADT) developed by Douglas T. Ross </Li> <Li> Yourdon structured method developed by Edward Yourdon . </Li> <Li> Structured analysis and system specification published in 1979 by Tom DeMarco . </Li> <Li> Structured systems analysis and design method (SSADM) first presented in 1983 developed by the UK Office of Government Commerce . </Li>

Explain the role of chart and its types in structured analysis