How to understand such a construction in Element UI :key="`country-${item.id}`"?

Question

Vue.js

Here is the context:

<el-option
                        v-for="item in countries"
                        :key="`country-${item.id}`"

from the context, in general, it is clear that keys of the 'country-15' type will be generated,

but the rules by which all this is written are not clear, how is this syntax generally regulated?

these strange quotes: `quotes` - is it from JavaScript or where?

this is ${item.id} - an expression - the meaning is clear what it is, but how does it combine with quotes `` and why is there a dollar sign?

Explain please who understands?

Thank you.

Answer 1

RTFM