Hi Rajneesh, This is Ramesh.
Both Local and Roaming folders contain per-user application data.
On a domain network, the files and subfolders under the "Roaming" directory are synced to other devices if you log in to your account on a different computer on the same domain.
The "Local" folder under "Appdata" doesn't roam to other devices. They're stored on the local machine.
The "LocalLow" folder is used by apps running with low integrity, such as web browsers. Even Office apps write to that folder, though don't usually run under low integrity level. Low-integrity apps can't write to the "Local" or "Roaming" folders.