Here is how the new text selection in Android M works: demo in motion4
Text selection is a core feature of every smartphone operating system, and it just has to be done well. In Android M, Google is changing the way we select, copy, and paste things to the better with a more intuitive and easy-to-use interface.
You still long-hold on a word you want to select and drag blue markers to adjust your selection (you can drag them word by word, or character by character like before), but now rather than having a toolbar at the top with obscure icons representing cutting, copying and pasting, you have a floating bar conveniently located right next to your selection with non-obscure easy-to-understand text buttons.
There is also a new three-dot button that brings up additional options for your selection: you can use this to quickly translate what you've selected (finally!), you can comment on your selection (if you're in a compatible app like Google Docs), or search for the selected text.
It's a more logical, more useful and just a more straightforward and intuitive way to deal with text selection, and we can't wait until it rolls out to devices. You can find a GIF demonstrating how the feature works right below.
source: Google Developers