The people who will take your call.
A directory tells you who exists. This tells you who you can actually reach — the members you are connected to, the requests waiting on you, and the graduates you almost certainly should know.
Mutual, and nothing happens without both sides
The rules are short on purpose, and they are enforced on the server rather than described in the interface.
Both sides agree
A request does nothing until the other member accepts it. Either of you can withdraw or remove it later, and removing a connection closes the message thread while leaving the history readable to you both.
Messaging follows the connection
Accepting opens a direct thread inside the portal. That is deliberately not the same as publishing a phone number — what contact details other members can see stays entirely under your control on your profile.
Introductions are named
Where a mutual connection exists, RITAA names them rather than showing you a degree. Knowing that a specific person knows you both is the difference between a cold request and a warm one.
Members are listed by department — CSE, IT, ECE, EEE, MECH, CIVIL, AIDS — and by graduating batch. Both are the fastest way to find someone who will recognise your name.