In a simple way the user-selection
serves to control the content that can be selected on the website.
Values
User-select accepts four values:
text - text can be selected
element - the text can be selected, being restricted to the limits of the element
None - text cannot be selected
auto – If the widget contains editable text, such as an input element or element with editable content, the text can be selected. Other forms of selection are determined by the value of the parent node.
Examples
-moz-user-select: none;
-moz-user-select: text;
-webkit-user-select: none;
-webkit-user-select: text;
-ms-user-select: none;
-ms-user-select: text;
-ms-user-select: element;
-moz
, -webkit
, -ms
these "markings" in front of the user-select
refer to each browser.
-moz
to Mozilla
-ms
for internet explorer
-webkit
for Chrome
When to use
You can use when you feel the need to control the content that is selected on the site.
In this website it shows how works the different types that the user-select
supports.
In this website has a table showing which browsers have support and their referred versions.
References:
MSDN
MDN
lol why edit and take the line I thank for helping? It’s against the rules to be polite?
– Andrey Hartung
Why is not relevant to the doubt.
– MeuChapeu
The @Meuchapeu response is quite complete, just to complement, check which (is) and which version(s) of browser you intend to use, as older versions do not allow.
– WyllianNeo