HOOKS-IN-DRUPAL

What is hooks ?

Hook is easier way to alter or extend the existing features
Which means that when Drupal provides a such a features . its also giving a extra features call as hooks.

Using hooks we can alter do some alteration based on the client requirement , we can do the extensions based on the requirement

Hook_entity_load :
When ever entity getting load this hook get called . we can alter the entity object using it (git ? ).

Hook_entity_view:
When ever we view the entity which means .if you consider entity is a node means
When you look at node/1 page or what ever node id page on that time this hook get called .

Hook_entity_insert:
When a new node is created that time this hook get called. (Its for insertion ).

Hook_entity_update:
Edit action of entity that time this hook get called .

Hook_entity_delete :
Delete action of entity that time this hook get called .

Like wise pre save , access

Hook_entity_create_access :
Hook entity create access (it means the creation of node page whether the users exist or not ,we can alter the access using this hook ).