This image shows only those interfaces (ports and sockets) that are important to our interest and point of view.
The rest of the small semiconductor parts of the motherboard are not of our interest, but for their designer.
In this post, only the names of all the interfaces have been mentioned.
Other than these interfaces, there are numerous chips and IC's for various functions as well.
They along with the functions of these interfaces would be described sometime later.
The components are so named:
A,B : PCI connector
C : CMOS battery
D : PCI-E (x1) connector
E : PCI-E (x16) connector
F : S/PDIF connector
G : Back-panel for I/O devices
H : 12V processor power (4-pin)
I : Rear chassis fan header (3-pin)
J : Processor socket
K : Processor fan header (4-pin)
L,M : RAM (channel A,B) sockets
N : Chassis intrusion header
O : Serial port header
P : Floppy Drive connector
Q : Main power connector (24-pin)
R : Parallel ATA (IDE) connector
S : Serial ATA (SATA) connectors
T : Front panel header
U : Alternate front panel power LED header
V : BIOS configuration jumper
W : Front USB headers
X : Speaker
Y : Front chassis fan header (3-pin)
Z : Front panel audio header