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diff --git a/doc/admin-guide/en-US/markdown/glossary.md b/doc/admin-guide/en-US/markdown/glossary.md
index 0febaff8fb8..0203319b08a 100644
--- a/doc/admin-guide/en-US/markdown/glossary.md
+++ b/doc/admin-guide/en-US/markdown/glossary.md
@@ -1,10 +1,10 @@
Glossary
========
-Brick
-: A Brick is the GlusterFS basic unit of storage, represented by an
+**Brick**
+: A Brick is the basic unit of storage in GlusterFS, represented by an
export directory on a server in the trusted storage pool. A Brick is
- expressed by combining a server with an export directory in the
+ represented by combining a server name with an export directory in the
following format:
`SERVER:EXPORT`
@@ -13,15 +13,22 @@ Brick
`myhostname:/exports/myexportdir/`
-Cluster
+**Client**
+: Any machine that mounts a GlusterFS volume.
+
+**Cluster**
: A cluster is a group of linked computers, working together closely
thus in many respects forming a single computer.
-Distributed File System
+**Distributed File System**
: A file system that allows multiple clients to concurrently access
data over a computer network.
-Filesystem
+**Extended Attributes**
+: Extended file attributes (abbreviated xattr) is a file system feature
+ that enables users/programs to associate files/dirs with metadata.
+
+**Filesystem**
: A method of storing and organizing computer files and their data.
Essentially, it organizes these files into a database for the
storage, organization, manipulation, and retrieval by the computer's
@@ -29,7 +36,7 @@ Filesystem
Source: [Wikipedia][]
-FUSE
+**FUSE**
: Filesystem in Userspace (FUSE) is a loadable kernel module for
Unix-like computer operating systems that lets non-privileged users
create their own file systems without editing kernel code. This is
@@ -38,26 +45,38 @@ FUSE
Source: [Wikipedia][1]
-Geo-Replication
+**Geo-Replication**
: Geo-replication provides a continuous, asynchronous, and incremental
replication service from site to another over Local Area Networks
(LAN), Wide Area Network (WAN), and across the Internet.
-glusterd
+**GFID**
+: Each file/directory on a GlusterFS volume has a unique 128-bit number
+ associated with it called the GFID. This is analogous to inode in a
+ regular filesystem.
+
+**glusterd**
: The Gluster management daemon that needs to run on all servers in
the trusted storage pool.
-Metadata
+**Infiniband**
+ InfiniBand is a switched fabric computer network communications link
+ used in high-performance computing and enterprise data centers.
+
+**Metadata**
: Metadata is data providing information about one or more other
pieces of data.
-Namespace
+**Namespace**
: Namespace is an abstract container or environment created to hold a
logical grouping of unique identifiers or symbols. Each Gluster
volume exposes a single namespace as a POSIX mount point that
contains every file in the cluster.
-Open Source
+**Node**
+: A server or computer that hosts one or more bricks.
+
+**Open Source**
: Open source describes practices in production and development that
promote access to the end product's source materials. Some consider
open source a philosophy, others consider it a pragmatic
@@ -76,7 +95,7 @@ Open Source
Source: [Wikipedia][2]
-Petabyte
+**Petabyte**
: A petabyte (derived from the SI prefix peta- ) is a unit of
information equal to one quadrillion (short scale) bytes, or 1000
terabytes. The unit symbol for the petabyte is PB. The prefix peta-
@@ -89,7 +108,7 @@ Petabyte
Source: [Wikipedia][3]
-POSIX
+**POSIX**
: Portable Operating System Interface (for Unix) is the name of a
family of related standards specified by the IEEE to define the
application programming interface (API), along with shell and
@@ -97,34 +116,79 @@ POSIX
Unix operating system. Gluster exports a fully POSIX compliant file
system.
-RAID
+**Quorum**
+: The configuration of quorum in a trusted storage pool determines the
+ number of server failures that the trusted storage pool can sustain.
+ If an additional failure occurs, the trusted storage pool becomes
+ unavailable.
+
+**Quota**
+: Quotas allow you to set limits on usage of disk space by directories or
+ by volumes.
+
+**RAID**
: Redundant Array of Inexpensive Disks (RAID) is a technology that
provides increased storage reliability through redundancy, combining
multiple low-cost, less-reliable disk drives components into a
logical unit where all drives in the array are interdependent.
-RRDNS
+**RDMA**
+: Remote direct memory access (RDMA) is a direct memory access from the
+ memory of one computer into that of another without involving either
+ one's operating system. This permits high-throughput, low-latency
+ networking, which is especially useful in massively parallel computer
+ clusters.
+
+**Rebalance**
+: A process of fixing layout and resdistributing data in a volume when a
+ brick is added or removed.
+
+**RRDNS**
: Round Robin Domain Name Service (RRDNS) is a method to distribute
load across application servers. RRDNS is implemented by creating
multiple A records with the same name and different IP addresses in
the zone file of a DNS server.
-Trusted Storage Pool
+**Samba**
+: Samba allows file and print sharing between computers running Windows and
+ computers running Linux. It is an implementation of several services and
+ protocols including SMB and CIFS.
+
+**Self-Heal**
+: The self-heal daemon that runs in the background, identifies
+ inconsistencies in files/dirs in a replicated volume and then resolves
+ or heals them. This healing process is usually required when one or more
+ bricks of a volume goes down and then comes up later.
+
+**Split-brain**
+: This is a situation where data on two or more bricks in a replicated
+ volume start to diverge in terms of content or metadata. In this state,
+ one cannot determine programitically which set of data is "right" and
+ which is "wrong".
+
+**Translator**
+: Translators (also called xlators) are stackable modules where each
+ module has a very specific purpose. Translators are stacked in a
+ hierarchical structure called as graph. A translator recieves data
+ from its parent translator, performs necessary operations and then
+ passes the data down to its child translator in hierarchy.
+
+**Trusted Storage Pool**
: A storage pool is a trusted network of storage servers. When you
start the first server, the storage pool consists of that server
alone.
-Userspace
+**Userspace**
: Applications running in user space don’t directly interact with
hardware, instead using the kernel to moderate access. Userspace
applications are generally more portable than applications in kernel
space. Gluster is a user space application.
-Volfile
+**Volfile**
: Volfile is a configuration file used by glusterfs process. Volfile
will be usually located at `/var/lib/glusterd/vols/VOLNAME`.
-Volume
+**Volume**
: A volume is a logical collection of bricks. Most of the gluster
management operations happen on the volume.