Is the 'cyber attack' a ransomware attack?
The firm is still referring to the cyber-attack as a "cyber incident" and is refusing to say publicly that it is ransomware, days after reporters confirmed it.
How did Royal Mail deal with the cyber attack?
Following the cyber attack, Royal Mail called in police and experts from the National Cyber Security Centre, part of spy agency GCHQ, to help deal with the fallout.
How has Ukraine's cyber-attacks changed over the past year?
Ukraine has suffered a threefold growth in cyber-attacks over the past year, with Russian hacking at times deployed in combination with missile strikes, according to a senior figure in the country’s cybersecurity agency.
What are Russia's cyber-attacks?
The attacks from Russia have often taken the form of destructive, disk-erasing wiper malware, said Viktor Zhora, a leading figure in the country’s SSSCIP agency, with “in some cases, cyber-attacks supportive to kinetic effects”.