screen is a screen manager. in years past if you had a long running job and it ws time for you to go home, you would start the job then throw it into the background and monitor the job via ps or log output or however you set up your job.
then came along screen
if you started a long running job at work and had to go home, you could resume your session and provide input to prompts if the job requested it. the other advantage of running a remote task or job in screen, is if your ISP suddenly decided to drop your connection, the job or task would continue uninterrupted