The earliest known drawing in human history – a red, cross-hatched pattern that looks somewhat like a hashtag – has been unearthed on a rock in South Africa.

Learn to recognise different circuit symbols with these interactive learning resources for KS2 Science students aged 7-11 from BBC Bitesize. ... Symbols are simplified drawings.

While ISA-5.1 deals with instrumentation and control content on various engineering drawings, including PFDs and P&IDs, this new TR will provide guidance and examples specific to PFDs and P&IDs.