GNU/Linux Desktop Survival Guide by Graham Williams
Desktop Survival Project Home Preface Advocacy History Distributions Installing GNU/Linux Basic Survival Wajig Applications AI, Machine Learning, Data Science Android - GNU/Linux Devices Audio Backup Booting CD Chinese ChRoot Clock Command Line Databases DIA Directories Disks EcoSysL Emacs Email Evolution Files File Systems Firewalls Floppy Disks FreedomBox Glade GNOME Graphics, Images, Photos Hardware Initialisations on Booting Installation Examples Internet IOT Java KDE Kernels Keyboard Konqueror KVM Switch LATEX Log System Login Magellan MATE Mathematics Memory Modems Mounting Devices MS/Windows Music MySQL Nautilus Networks Nextcloud Network File System NFS NT File System Oracle Packages Partitions Passwords PDF Power Management PPP Presentations Printing Python R Remote Desktops Rsync Samba Scanning Science Screens Security Spreadsheet SSH Swap Teradata Data Warehouse Themes TV Unity USB Version Control Video Virtualization Voice over IP WebCam WordPress Web Sites Word Processing and Printing X XML Troubleshooting Index

CLICK HERE TO VISIT THE UPDATED SURVIVAL GUIDE

Screens: Saving and Locking

Updated 140103

Screen savers and lock screens are common applications found in many operating systems. The original purpose of the screen saver was to save the screen from image burn-in. This was particularly an issue with older cathode ray tube (CRT) terminals which were susceptible to phosphor burn-in. An image that was on the screen for some (long) time would leave a ghost image on the screen permanently. A screen saver would instead display a regularly changing image. The popular xscreensaver provided an impressive range of weird and wonderful patterns to display on the screen and save it from burn-in, all the while using compute power to generate some of the intricate patterns.

As of about 2011 though, the technology used for screens has changed significantly. With the development of liquid crystal displays (LCDs) the issue of burn-in has considerably reduced (and some say been solved). There is no longer any need to use fancy screen savers. In fact using one will consume power whilst simply automatically turning off the screen is more environmentally friendly. The gnome-screensaver, for example, will simply blank the screen after a period of time and put it into power saver mode.

The extra functionality often found with a screen saver is to lock the screen to prohibit unauthorised access whilst allowing a user to remain logged on.