This is the 846th most frequent Arabic word.
لحماية
"To protect" or "for protection."
Here, لحماية indicates 'for the protection of' or 'for protecting' referring to the purpose of using antivirus programs.
تستخدم البرامج المضادة للفيروسات لحماية الحاسوب.
Antivirus programs are used to protect the computer.
The word لحماية is used to explain the goal or reason behind using strong passwords, which is to secure personal data.
تحتاج البيانات الشخصية إلى كلمات مرور قوية لحمايتها.
Personal data requires strong passwords for its protection.
In this context, لحماية describes an intended result or purpose of studying environmental sciences, which is the protection of the planet.