网址 (wǎng zhǐ) refers specifically to the web address or URL of a website, like 'www.example.com'. It differs from 网站 (wǎng zhàn), which is the website itself (the collection of pages), and from 网页 (wǎng yè), which is a single web page. 地址 (dì zhǐ) is a broader term for any address (home, email), while 网址 is only for online addresses.