Land offers different habitat for different species. For instance, grassland, forest, mountain, desert and coastal lands. Each of these life zones has its own kinds of creatures. In fact, almost all are somehow linked with one another by what they eat or what eats them. The biologists call this link a food chain. Thus each of these creatures offers food chains making 
up a food web special to that place. 

Most of the sizeable animals on land are known to us. Yet there are many more we are not aware of. There are some thousands which move on the grounds but beyond the range of our sight. Starting from a stroll down the meadow in the morning you will find a great variety. 
As you put your steps you run into some hundreds of movements around you. Some shrew
 pops down holes, a spider scuttles through the grass, an earthworms squirms its way 
beneath your feet. 

The springtails will dance around in a great fuss. Advance yet another step. Maybe a ground rodent downs its head to burrow deeper into the hole. And strange you come to know very little, if at all, about these fuss. What you see at best is those birds hopping on the twigs of a nearby tree. Keep your eyes wide open. And many more creatures will be caught in your eyes. 
Say the pupa sticking to a grass leaf, a grass hopper playing around,  a dragon fly buzzing in its aimless loops of flight. And so on. Indeed these are just a sample of what comprise the animals on land. These animals can be classified into various groups. 
Based on food habit there are two types herbivorous and carnivorous. 
Those who eat plants are herbivorous. The carnivorous
live on the flesh of other animals. Human consume both and may be called omnivorous.
The classification may also be done on the basis of the habitat they live in. Let us start with
the life in the grasslands. In every continent except Antarctica there were 
once vast areas of grassland. Some have been ploughed up and sown with crops. Some have been populated indiscriminately by turning them into villages and cities. Still others survive, 
with all their wild habitations. 

Though trees grow here and there, forests cannot thrive. There is too little rain for their 
thirsty roots. And the thick bed of soil, that helps the plants to grow, is also absent. 
Grasslands house many creatures like rodents, lizards and snakes, seed eating birds and insects. For grass eating mammals, these lands are huge food bowls. But some creatures lack hiding places from big cats or wolf-like animals that prey upon them.