What's an account? When a computer is used by many people it is usually necessary to differentiate between the users, for example, so that their private files can be kept private. This is important even if the computer can only be used by a single person at a time, as with most microcomputers. Thus, each user is given a unique username, and that name is used to log in. There's more to a user than just a name, however. An account is all the files, resources, and information belonging to one user.
They include biochemical, clastic and evaporative sedimentary rocks. Biochemical sedimentary rocks are formed from organic processes that involve living organisms producing the sediments. These living organisms can be snails and clams whose discarded calcium carbonate shells can form limestone.
The rock cycle is the process in which igneous, sedimentary, and metamorphic rocks are changed over time. Igneous rocks are formed by volcanic activity. Metamorphic rocks are igneous, sedimentary, or other metamorphic rocks that have been changed by heat, pressure, chemical means, or a combination of all or some of the above. Sedimentary rocks are formed from the weathering of all of the rock types and the cementing, compressing, or recrystallization of the sediments.