It means you can't use the keyboard unless you press a certain combination of buttons in order to unlock it. It's so the phone wouldn't accidentally dial someone while in your pocket.
It varies from brand to brand, but you usually pres or hold the * or # or 0, and a message appears on the screen.
Password lock
A land line is a house phone, that must be attached to a phone line or a device connected to a phone line. A cellular phone is a mobile phone that allows you to move freely anywhere.
The spelling is "cellular phone" which is normally shortened to "cell phone."
In Case (of) Emergency
Cellular is an adjective; phone is a noun.
It can be either an adjective: A cellular building, a cellular phone; or a new noun, meaning "cellular phone".
"My phone number is"
how do i lock my phone
Cellular phone
my spice phone is lock what i do
reset phone lock
phone lock