What does it mean when they said that a phone has 1gb of RAM ?
A phone having 1GB of RAM means that it has 1 GB worth of random access memory that is used to handle the phones applications. Some RAM will also be reserved for the GPU.
Your phone has 1 gigabyte of random access memory. Basically the amount of RAM you have determines how much your device can handle. Most computers have 2-4 gigs RAM