Job Recruitment Website - Job information - What is the difference between an official website and a portal website?

What is the difference between an official website and a portal website?

Official website: A large-scale institution or enterprise, government website, and externally declares its website as its official website. For example, "This information is from NOKIA's official website." It emphasizes that it is their own website (I think) but it is actually a corporate website.

Portal website: such as 163, sina and other comprehensive websites, or a professional website such as "51JOB Recruitment", "PC-ONLINE" and other websites.