XPath: current context and recursive descent, what does it mean?

Question

XPath

Hello!
What do these two parameters mean:
. - current context
.// - recursive descent (zero or more levels from the current context)
Please provide some simple examples.

Answer 1

the current context is the node to which the request is being applied.
Let's say we have a document:

<root>
    <el1>1</el1>
    <el2>
        <el1>2</el1>
    </el2>
</root>

and we apply some query to it, then the current context will be root
, then we can walk through the tree:
root / el1 will return us <el1>1</el1>because it only searches one level.
root//el1 will return us <el1>1</el1>and <el1>2</el1>because it searches at all levels of nesting.

Answer 2

well, do seo and you will be on the second page

Answer 3

It was 2017...
Where did you find such a site design at all?)