T-Chart
A T-Chart is a graphical way of representing two facets of a topic. The topic or concept is written at the top of the chart and contrasting elements are listed down on either side of the "T". It helps to make decision by comparing advantages and disadvantages of a certain thing; it helps to enumerate problems and solutions associated with an action etc. It helps in comparing two things, identifying similarities on the left and differences on the right; positives vs. negatives, leaders vs. managers etc.

Mind-Map
Mind-Map is a powerful graphical technique to represent relationships between ideas or other pieces of information. It assists in faster information sharing with audiences. It also helps to visually represent their understanding of a concept being discussed. The structured approach helps one to present the information easily and display the relation between the various pieces of information. This activity helps students to collaboratively create a mind-map about a given topic.