A protocol is a particular set of rules for having a conversation between two computers to convey a specific set of information. It is an agreement between the communicating parties on how the communication is to proceed. Violating the protocol will make the communication more difficult.
An example of protocol would be TCP/IP. The specifics of the above would detail the addressing format, number of bits used, methods to decide grouping, size of data chunks and more
Standard : A standard (and in the networking arena, many protocols are standards) is a document that specifies something that has the overwhelming support and agreement of the standards making bodies.
An example of standards would be 802 standards. One of them, 802.3u, lays down the specifications related to FastEthernet. So, if anyone were to design a hardware or software related to FastEthernet, they would have to follow those specifications.
Some of the standards making organizations are given below: