You would have seen that all the materials occupy certain space. The total space occupied by any piece of matter is referred to as its volume. The SI unit used for volume measurement is the volume of a cube of side 1m each. We call this unit as one cubic metre, abbreviated as 1m³. To measure smaller or larger volumes, we use other appropriate units like cm³, mm³, or km³.
Now, let us study how to measure the volume of different types of bodies.

Volumes of regular solids
To measure the volumes of regular solids like cube, sphere or cylinder etc., we have well known formulae. Some of such formulae these are given in Table.

You would have seen a milkman or a kerosene dealer using volume-measuring vessels as shown in Figure.These are generally cylindrical or conical in shape and have their capacity in litres. A litre is one-thousandth part of the SI unit of volume, i.e. m3.
1 litre = 10^-3m³

Taking a reading of liquid level in a measuring cylinder
It is observed that liquids like water form a concave meniscus as shown in Fig. 1.17a, while those like mercury form a convex meniscus Fig. 1.17b. Now, question arises how to take correct readings of the liquids in such cases. We must keep our eyes in line with the flat middle part of the liquid while taking a reading. If we just look at the measuring cylinder and water level we will get a wrong reading.