You can have a brief and detailed version of your resume as some companies do want one and want to know details such as your salary for past employers. Have different versions with you when completing job applications, saves you time and helps you to keep track of information. It takes just one bit of wrong information which you may have forgotten and took a guess at to eliminate you from getting an interview. Yes, a lot of employers are not prescreening job applicants before contacting them for interviews.