Should each MySQL table have an auto-incrementing primary key?

Question

• I understand the meaning of primary keys.
• I understand the meaning of indices.

Should each MySQL table have an automatically incrementing primary key (ideally with an INT field type)?

Update

@Raj More answer seems most effective. However, the problem when I think about this is how this auto-incrementing primary key identifier will relate to other tables. For instance:

Table 1

ID  |   firstname  |   lastname | email
----------------------------------------
1   |    john      |   doe      | [e-mail]
2   |    sarah     |   stow     | [e-mail]
3   |    mike      |   bro      | [e-mail]

table 2

ID  | memberid |    display      |    address
--------------------------------------------
1   |    1     | funtime zone    |   123 street
2   |    3     | silly place llc |  944 villa dr 

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Answer 1

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Answer 2

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Edit

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Answer 3

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EDIT: Added more in the previous sentence.