What are some big electricity wasters? Like if I keep my computer on overnight, does that waste electricity? and should i be unplugging things such as tv’s and lamps every time i’m not using them? any info would be great… thanks in advance!

(may be broke/outdated!)
What are some big electricity wasters? Like if I keep my computer on overnight, does that waste electricity? and should i be unplugging things such as tv’s and lamps every time i’m not using them? any info would be great… thanks in advance!