This is the 13286th most frequent Russian word.
москвичам
"Москвичам" means "to Muscovites" or "for Muscovites."
This sentence uses 'москвичам' in the dative case to describe the recipients of the information.
Эта информация особенно полезна москвичам.
This information is especially useful for Muscovites.
Here, 'москвичам' is used in the dative case again to describe the beneficiaries of the assistance.
Помощь москвичам в сложной ситуации оказалась решающей.
Help for Muscovites in a difficult situation turned out to be crucial.
In this sentence, 'москвичам' refers to the people the letters will be sent to, showing its function as the indirect object in the dative case.