Do I need to unlock the smartphone?

pennypincher2013

An ex coworker (he moved onto better job) gave me his old smartphone (he got a new one). I have a new sim from TalkTalk (I got a deal) I'd like to use with the phone. Do I need to unlock the phone first before registering the sim? I don't want to register it and it fails to work because it needs to be unlocked.
I've never owned a smartphone before
If I register the sim to that phone will I also be able to use the sim with my brick mobile?

grumbler

Not all phones are locked.
If yours is locked to any network except O2 that, I believe, TalkTalk use now, then you need to unlock it.
You don't need to 'register' the SIM.
SIM can be moved from one phone to another if they take the same sized SIM. Unlike your 'brick', some smartphones require micro- or nano-SIM.

J_B

Maybe tell us what 'smart phone' it is?

forgotmyname

All my Voda contract phones are unlocked. (not sure on apple phones though)

pennypincher2013

The smart phone is Samsung - I have no idea what model it is.
TalkTalk have said I have to register my details with them. I think that's where I was confused about 'registering' the sim.
I have no idea what the network was.
My ex co-worker has LOADS of phones left of his phone. lol! I have tried to delete them but when I turn the phone back on they reappear!