Typos:
* "Some computers store integers as 32 bits field, others use 64 bits field and the same problem arises with floating point **number**." => "Some computers store integers as 32 bits field, others use 64 bits field and the same problem arises with floating point **numbers**."
* "the `Application layer` **that contains** the mechanisms that do not fit in neither the Presentation nor the Session layer." => "the `Application layer` **contains** the mechanisms that do not fit in neither the Presentation nor the Session layer."