2. Introduction
Statistics is the study of
the collection, organization,
analysis, interpretation, and
presentation of data. It
deals with all aspects of
this, including the planning
of data collection in terms of
the design of surveys and
experiments.

3. History
The use of statistical
methods dates back at least
to the 5th century BC. The
earliest writing on statistics
was found in a 9th century
book entitled: "Manuscript
on Deciphering
Cryptographic Messages",
written by Al-Kindi. In his
book, he gave a detailed
description of how to use
statistics and frequency
analysis to decipher
encrypted messages, this
was the birth of both
statistics and cryptanalysis,
according to the Saudi
engineer Ibrahim Al-Kadi.

4. Collection Of Data
1. When information is
collected by the investigator
herself or himself with a
definite objective in mind, is
known as PRIMARY DATA.
2. The information was
gathered from a source which
already had the information
stored, the data obtained in
this way is known as the
SECONDARY DATA.

5. Presentation of Data
The Type Of Data we
collected is known as
raw data. We can
present it in a
number of ways like:
1. Frequency Table
2. Bar Graphs
3. Histogram
4. Frequency
polygon
5. Line Graph.
6. Pie chart

6. A graph consisting of
rectangles whose area
is proportional to the
frequency of a variable
and whose width is
equal to the class
interval. It was first
introduced by Karl
Pearson.
It is said to be derived
from the Greek histos
'anything set upright'
(as the masts of a ship)
and gramma 'drawing,
record, writing'.

7. In a Frequency Polygon, a
line graph is drawn by
joining all the midpoints of
the top of the bars of a
histogram. A frequency
polygon gives the idea about
the shape of the data
distribution.The two end
points of a frequency
polygon always lie on the x-
axis.