It is easier to learn and reproduce from examples than from instructions. So here are some examples using google charts:

Pie Chart

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=p3" is for specifying 3D pie chart
"chd=t: data1,data2...." is for specifying data
"chco=F778A1,ADDFFF" is for specifying the colours of chart
"chtt=Male%20Students%20Enrolled%20For%20Bachelor" is for specifying chart title
"chts=F6358A,20" is for specifying font size and colour of chart title
"chs=550x300" is for specifying chart size
"chl=AGRI|ARTS|BIO|Buis.A" is for specifying label for pie chart

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=p3" is for specifying 3D pie chart
"chd=t: data1,data2...." is for specifying data
"chco=92BF23,cc0000" is for specifying chart colours
"chtt=Female%20Students%20Enrolled%20For%20Bachelo" is for specifying chart title
"chts=92BF23,20" is for specifying font size and colour of chart title
"chs=550x300" is for specifying chart size
"chl=AGRI|ARTS|BIO|Buis.A" is for specifying label for pie chart

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=pc" is for specifying pie chart
"chd=t: data1,data2...." is for specifying data
"chco=FDEEF4,B93B8F" is for specifying chart's colour
"chtt=Male%20Students%20Enrolled%20For%20Bachelors" is for specifying chart title
"chts=B93B8F,20" is for specifying font size and colour of chart title
"chs=550x300" is for specifying chart size
"chl=CHEM|CMRC|I.T|D.S|ENG|LAW|MHS|NRSNG|PHRM|P.A|ST|SST|VET|BSC.PAS" is for specifying pie chart label

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=p3" is for specifying pie chart
"chd=t: data1,data2...." is for specifying data
"chco=7F462C,E77471" is for specifying chart's colour
"chtt=Female%20Students%20Enrolled%20For%20Bachelors" is for specifying chart title
"chts=C85A17,20" is for specifying font size and colour of chart title
"chs=550x300" is for specifying chart size
"chl=CHEM|CMRC|I.T|D.S|ENG|LAW|MHS|NRSNG|PHRM|P.A|ST|SST|VET|BSC.PAS" is for specifying pie chart label

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=p3" is for specifying 3D pie chart.
"chd=t: data1,data2...." is for specifying data
"chco=E55B3C,CFECEC" is for specifying chart colour
"chtt=Males%20Enrolled%20For%20Master%20Degree" is for specifying chart title
"chts=E55B3C,20" is for specifying size and colour of chart title
"chs=550x300" is for specifying chart size
"chl=AGRI|ARTS|BIO|Buis.A" is for specifying chart label

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=pc" is for specifying pie chart.
"chd=t: data1,data2...." is for specifying data
"chco=C48189,7F5A58,F9A7B0" is for specifying chart colour
"chts=C48189,20" is for specifying size and colour of chart title
"chtt=Females%20Enrolled%20For%20Master%20Degree" is for specifying chart title
"chs=550x300" is for specifying chart size
"chl=AGRI|ARTS|BIO|Buis.A" is for specifying chart label

"http://chart.apis.google.com/chart?" is the Chart API's location
"&" separates parameters
"cht=p3" is for specifying 3D pie chart.
"chd=t: data1,data2...." is for specifying data
"chco=FF0000,151B8D,00FFFF" is for specifying chart colour
"chtt=Females%20Enrolled%20For%20Master%20Degree" is for specifying chart title
"chts=FF0000,20" is for specifying size and colour of chart title
"chs=550x300" is for specifying chart size
"chl=AGRI|ARTS|BIO|Buis.A|CHEM|CMRC|I.T|D.S|ENG|LAW|MHS|NRSNG|PHRM|P.A|ST|SST|VET|BSC.PAS" is for specifying chart label