I am interested in doing some core Java certifications but I do not know where to start from.Previously it was SCJP but then I heard it was changed to something else.On Oracle's website I see OCA and OCP.I have also heard about OCPJP but I am still not clear where to start.Kindly guide me on this.Should I start with OCA or OCP?.Are these mandatory for advance level certifications like Web Component Developer?.Thank you