electronic footprint
noun [ C ] uk/el.ekˌtrɒn.ɪk ˈfʊt.prɪnt/ us/i.lekˌtrɑː.nɪk ˈfʊt.prɪnt/
电子痕迹（指发送电子邮件、使用信用卡等留下的记录）
something electronic, such as sending an email, using a credit card, etc., that shows where you have been and what you have been doing
Every website you visit leaves an electronic footprint of your surfing habits. 你所访问的每个网站都会留下你浏览习惯的电子痕迹。