هذا البرنامج للتحكم في الجهاز.

هذا is the demonstrative for a near, masculine singular noun: this.

The noun برنامج is grammatically masculine singular, so Arabic uses هذا:

• هذا البرنامج = this program

If the noun were grammatically feminine, you would usually use هذه instead.

After a demonstrative like هذا, Arabic normally uses a definite noun:

• هذا البرنامج = this program

That is the normal way to say it in Arabic. Even though English would not say this the program, Arabic does use the definite article here.

By contrast:

• هذا برنامج means this is a program

So the version with الـ is a noun phrase meaning this program, while the version without الـ is more like a full identifying sentence.

Because this is a present-tense nominal sentence in Arabic. In the present tense, Arabic usually omits the verb to be.

So:

• هذا البرنامج للتحكم في الجهاز literally looks like:
• this program for controlling the device

But naturally it means:

• this program is for controlling the device

The idea of is is understood without being said.

It is a nominal sentence:

• هذا البرنامج = the topic/subject, this program
• للتحكم في الجهاز = the predicate, for controlling the device

So the whole structure is:

• This program
  • is for controlling the device

للتحكم is made of two parts:

• لِـ = for
• التحكم = control / controlling

So للتحكم means:

• for control
• for controlling
• to control (depending on natural English wording)

Here التحكم is a verbal noun (also called a maṣdar) from the verb تَحَكَّمَ = to control.

Because it combines:

• لِـ = for
• الـ = the

So:

• لِ + التحكم → للتحكم

In writing, both ل letters appear.

In pronunciation, things change a little because ت is a sun letter. So the article is not pronounced as a clear l sound there. The word is pronounced approximately:

• lit-taḥakkum

So:

• written: للتحكم
• pronounced: roughly lit-taḥakkum

Here في links control to the thing being controlled.

Literally, في often means in, but with words like التحكم it can be understood more naturally as:

• control of the device
• control over the device
• controlling the device

So in this sentence, في is part of the normal Arabic expression with التحكم.

الجهاز is definite: the device.

Arabic often uses the definite article when the thing is:

• already known from context
• specific
• understood by speaker and listener

So في الجهاز suggests a particular device or a device already being talked about.

If you said في جهاز, that would mean in a device or in some device, which is less likely here.

A fully vocalized version is:

هٰذَا الْبَرْنَامَجُ لِلتَّحَكُّمِ فِي الْجِهَازِ

You can break it down like this:

• هٰذَا
• الْبَرْنَامَجُ
• لِلتَّحَكُّمِ
• فِي الْجِهَازِ

In fully inflected MSA, the endings are:

• الْبَرْنَامَجُ → -u because it is the subject/topic of the nominal sentence
• التَّحَكُّمِ → -i because it comes after the preposition لِـ
• الْجِهَازِ → -i because it comes after the preposition في

So the grammatical pattern is:

• subject in the nominative
• nouns after prepositions in the genitive

A careful pronunciation is approximately:

hādhā al-barnāmaju lit-taḥakkumi fī al-jihāzi

A few notes:

• هذا = hādhā
• البرنامج keeps the al- sound because ب is a moon letter
• للتَّحكُّم is pronounced with a doubled t sound: lit-taḥakkum
• الجهاز keeps al- as well: al-jihāz

So the sentence flows roughly like:

hādhā al-barnāmaju lit-taḥakkumi fī al-jihāzi