Oligosaccharides
( Greek oligos = few). On hydrolysis, they generally give two to nine monosaccharides( same or different) and are further classified as disaccharides, e. g., sucrose, maltose, lactose, trisaccharides and so on.
C12H22O11 is a disaccharide because it gives two monosaccharides.
The bond formed between two monosaccharides is called a glycosidic bond and normally it is( 1, 4) bond.
Sucrose is most abundant in plants and known as cane sugar or table sugar or invert sugar as equimolar mixture of glucose and fructose is obtained by hydrolysis of sucrose.
Trisaccharides Raffinose( C18H32O16)
Polysaccharides
These are polymers of monosaccharides. Examples are starch, cellulose, glycogen, etc.