kono shiryou ni wa, chizu mo haitte imasu.

topic particle

Breakdown of kono shiryou ni wa, chizu mo haitte imasu.

• この: this
• に: location particle
• 地図ちず: map

Questions & Answers about kono shiryou ni wa, chizu mo haitte imasu.

Why is it に は instead of just に?

に marks the place something is in or inside.
So 資料に入っています would mean is in the materials/document.

Adding は after に gives that location a topic or contrast nuance:

• この資料には = as for this material / in this material
• It can suggest something like at least in this material or in this one, ...

So には is very common when the speaker wants to highlight the location as the topic.

What does も mean here?

も means also or too.

So 地図も入っています means:

• A map is also included
• There is a map in it too

This implies that the material contains other things as well, and the map is one more item.

Compare:

• 地図が入っています = A map is included
• 地図も入っています = A map is included too

Why is it 入っています instead of just 入ります?