Data security involves protecting data from threats like loss, corruption, hacking, or destruction. Key threats include system crashes, faulty storage, accidental or malicious deletion or alteration of files. Measures to keep data secure include regular backups, anti-virus software, access controls like passwords, safe storage of removable media, and data encryption. Data can be transferred between computers in standard file formats and transmitted digitally at high speeds globally. Common file types depend on the creating application, and files may need to be translated between types using import/export or the clipboard to be used in other programs.