It is not necessary that Anchor text should be unique. You can also take keyword variation.
Yes, it is a good practice is most cases.
In general, it's still a best practice to obtain and use keyword- and topic-specific anchor text when possible. If too many links to a page all use the same anchor text, even if they're on your own site, Google might sense spammy behavior.
Hi, An exact match anchor text is when you use the same words as the targeted keywords for your entire page. In the early days of SEO, using exact matches enough times on a single page almost guaranteed that your post would do well.
Yes my dear friend the anchor text must be unique. So that google crawlers relate that there is no spamming and the chances of ranking must be higher.
The link text should be unique among all of the links on the page, or alternatively the unique function of the link should be able to be determined from the link's context. This helps in determining what a link's function is and differentiating it among similar links
Not really. If 10 website owners are targeting "X" keyword, they will target the same keyword in their anchor.
We use Anchor Text on keywords targeting which is relevant to the content of the page. So place the anchor text on relevant keywords and don't use it more than one time.
Anchor text matters greatly to SEO, as it can indicate to Google what a page is about. In fact, using anchor text as a ranking signal is included in several Google patents. Not using anchor text or using generic anchor text, such as "click here" is generally considered a poor SEO practice.