Doug Andrea, the chief executive of Andrea Electronics, discusses his company’s 75-year history in the audio industry. Quentin Hardy, the deputy technology editor of The Times, explains what “Big Data” is and how it’s being used to put online advertisements in front of people. The weekly news roundup includes Nokia and Microsoft’s new mobile phone venture, Netflix’s continued woes, a new round of “Grand Theft Auto,” and computer scientists cracking the cipher of an 18th-century manuscript. The Tip of the Week offers a quick way to clean up old bookmarks in Firefox.