### Theory:

Have you ever visit a library?

If yes, you might have seen that the books are arranged in the subject genre-wise. If we need any history book, we can find that in the history section. We cannot find economics books in the arts section. We are using this method to identify and collect a book quickly.

Similarly, the data also maintained and represented in a particular manner to give a better and easy understanding to the user.

One of the many representation ways is called a tally mark.

The tally mark gives a precise understanding of the data figures. Let's see an example to understand this concept.

The teacher collected the below data from $$20$$ students of their favourite sports. The teacher used a tick mark $✓$ to represent a number of students.

 Favourite sports The number of students liked Frequency Cricket $$10$$ Football $$6$$ Volleyball $✓\phantom{\rule{0.147em}{0ex}}✓\phantom{\rule{0.147em}{0ex}}\phantom{\rule{0.147em}{0ex}}$ $$2$$ Basketball $✓\phantom{\rule{0.147em}{0ex}}✓\phantom{\rule{0.147em}{0ex}}$ $$2$$

Though the tick mark was easy to represent, we could not count each and every tick mark, which is tedious and time taken. For example, if $$10$$ tick mark is plotted, we have to count ten tick marks individually, then only we can confirm it.

But in the tally mark method wherein a first sight, we can say the count of the data.

 Favourite sports The number of students liked Frequency Cricket $\overline{)\mathit{IIII}}\phantom{\rule{0.294em}{0ex}}\overline{)\mathit{IIII}}$ $$10$$ Football $\overline{)\mathit{IIII}}\phantom{\rule{0.147em}{0ex}}\phantom{\rule{0.147em}{0ex}}I$ $$6$$ Volleyball $\mathit{II}$ $$2$$ Basketball $\mathit{II}$ $$2$$

The speciality of the tally mark is once it reaches the $$4$$ it strikes out and becomes as $$5$$, so whenever the tally mark is a strikeout, we should read it as $$5$$. This precise elaboration gives the best representation of the data.