“How do you know which server to select?”
A coworker is showing you how to use a software system at work. While showing you how to connect to the company's network, she chooses a server from a list. You want to know why she picked that one.
How do you know which server to select?
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How do you know (clause)?
Use this phrase to learn about something that a person seems to understand better than you:
How do you know which one to choose?
How do you know where to go?
How do you know when it's time to flip it?
a server
A "server" is a computer that other computers connect to.
Websites run on servers. A lot of companies also have servers to hold information that's shared between different employees.
select (something from a list)
The word "select" means "choose":
Which option have you selected?
"Select" is a little more formal than "choose".
It also suggests choosing something from a list or a group of options, like a menu. "Choose" can be used in the same way as "select". But you can use "choose" to talk about yes-or-no choices:
I chose not to go.
It's less common to use "select" in this kind of situation.