an architect designs the blueprint

an architect designs the blueprint of a building before it is constructed. similarly a systems analyst designs the logic of a computer program.
an architect will designs the blueprint using architectural drawing tools and techniques. similarly a systems analyst will design a computer program using programming tools and techniques called algorithms and flowcharts
a building contractor will construct the building according to the design and specifications in the blueprint laid down by the architect. similarly, a computer programmer will make a computer program according to the algorithms and flowcharts made by the systems analyst.