Taproot, It is the primary root from which secondary roots ( rootlets) derive from.
Fibrous roots do not have a primary root. They show almost the same size and width.
Elongated taproots offer a very fat primary root because they accumulate food it.
Tuberoid roots or tuberous roots are fibrous roots that became fat because of the accumulation of nutrients. (More information)
Branched roots do not have a primary root. They resemble to the branches of a tree.
OTHER TYPES OF ROOTS
Besides the more usual roots named above, we should consider those ones that are a bit special. Those not inserted into the soil, either because they are in the open air or because they live inside the water. These special roots are the following: