Formatting Date and Time By Custom

Symbol	The resulting display
General	Digit serial number of days starting from the early 20th century. For example on 23 Dec 2007 39 439 will be displayed as numbers.
Date
d	Figures date from 1 to 31 without starting with 0.
Dd	Figures date from 01 to 31 starting with 0.
Ddd	Name days in abbreviated form, for example, Sun, Mon, Tue.
Dddd	Name day in the form of the writing intact, for example Sunday, Monday, Tuesday.
Month
M	Figures from 1 to 12 months without beginning with 0.
Mm	Figures month from 01 to 12 with the prefix 0.
Mmm	Abbreviation of writing the name of the month, the example of Jan, of Feb, Mar.
Mmmm	Writing the name of the month as a whole, such as January, February, March.
Year
Yy	Writing only a two-digit figures last year alone, from 00 to 99 (note, in 1900 and 2000 in two equally digit display with 00).
Yyy	Writing numbers in full four-digit year.
Jam (Hour)
h	Figures from 0 to 24 hours without the first 0.
hh	Figures hours from 00 to 24 starting 0.
Minute
m	The minutes from 0 to 59 without the first 0.
mm	The minutes from 00 to 59 beginning with 0.
Second
s	A number of seconds from 0 to 59 without the first 0.
ss	A number of seconds from 00 to 59 starting 0.
[ ]	Writing hours greater than 24, writing minutes and seconds over 60.
AM/PM
A/P	Displays clock with AM or PM time information behind.

Symbol m used for months or minutes. Excel will differentiate writing m for minute when following symbols h for hours. If m standing in front or standing behind the symbol d, will be considered as a month.

Format	Display
dddd	Saturday
ddmmmmyyyy	09 August 2007

Hiding Zero Value
If in a table appearance zero value is not desired, you can hide a zero value in two ways.

Hiding Zero Value in a Worksheet
Click the Microsoft Office button and click Excel Options. At Advanced, under the Display options for this worksheet, deactivate the option "Show a zero in cells that have zero value".

Through this manner specified definition will apply to all cells in the active worksheet. If you want to define for several worksheets simultaneously choose the tabs and the title of the new worksheet, use the steps above.

Hiding Zero Value in a Certain Cells
In the cells that null values do not want to appear, use the following simple custom format #, ###. In principle, only the # sign stating the number of digits of a display of numbers only, so if the value is zero, then it is not displayed. Unlike the format #, ## 0 when the value of zero will be displayed as 0.