Currency: Saudi Riyal
Language: Arabic is the official language, and very few people speak English except in major cities of Riyadh and Jeddah and Dammam.
Visa: Pakistanis need to prearrange a visa.
Climate: Saudi Arabia has a desert climate with very high day-time temperatures and a sharp temperature drop at night. Average summer temperatures are around 45 °C. I do not recommend visiting during summer.
Trivia: Saudi Arabia is world’s 12th largest country by land.
Halal food is available everywhere as it is an Islamic country,
Road infrastructure is good and thanks to lower oil prices in the country; you can easily afford road trips.
Depending on the city you are visiting, KSA has several accommodation options with hotels starting from 30US $. There are some listings available on Airbnb as well (use this link to get 25$ off).
You can also check other travel resources which will help you plan your trip better.
The is no nightlife speaking in western terms.
To go or not to go:
Apart from holy pilgrimage, there is no point visiting it.