Should robots.txt have separate sections for each user-agent?

Question

HTML

Is there any difference in terms of search engine optimization between this:

User-agent: *
Disallow:

and this:

User-agent: Yandex
Disallow: 

User-agent: Googlebot
Disallow:

?
The site is a simple business card. Am I doing it right that I do not prohibit anything for indexing?

Answer 1

In your situation, in terms of optimization, most likely there is no difference.
It may be necessary to use different User-agents to solve certain problems.
For example:
When using User-agent: * - Adsense bot (User-agent: Mediapartners-Google) cannot display ads in blocked sections of the site. In this case, it is logical to use different sections.
For Google and Yandex, it may also be necessary to use different instructions, but until you have it, don't worry.

Answer 2

User-agent: * - any bot. Read at the
same time .

Answer 3

There are general rules for all bots, but each bot supports additional sets of rules.
If we use only general directives, then it is enough for * to specify.

Answer 4

only if in a certain browser you got an index of an unrequired section, usually in Google, therefore for it you write a separate rule to prohibit such and such a section forcibly, otherwise not.