Error bars are often used on graphs to show statistical comparisons.
You use a bar graph when you need to show comparisons between items. (categories)
a bar graph or line plot
A graph refers to a diagram that shows the relation between variable quantities. Bar graphs are often used to show statistical comparisons because they show the relevant data side by side.
A graph
You would use a bar graph to show data changes over time or to show comparisons among items. A line graph can also be used to show data changes over time or comparisons. A pie/circle graph would be used to show the relative amount/size of items in a data set. A scatter plot is used to show trends and similarities in a large number of data points. This link might be useful too. http://office.microsoft.com/training/training.aspx?assetid=rc011097791033&ofcresset=1
Every graph shows comparisons of some kind or another.
You use a bar graph when you need to show comparisons between items. (categories)
Bar charts are good for comparing related items. Answer: for Excel it is best known as a column chart.
A textual graph is a graph where the results and comparisons are written out instead of expressed in numbers. A textual graph has a list of comparisons divided into columns much like a pros and cons list.
Error bars are often used on graphs to show statistical comparisons.
line or bar graph