Halal is an Arabic word which means allowed or lawful. In the case of diets and foods, most of them are considered to be halal unless they are specified or mentioned in the Quran or Hadith (sayings of Prophet Muhammad Saw). Human beings can’t change the unlawful (Haram) into lawful (Halal). It is also unlawful to make the lawful as unlawful.
The other name of Halal meat would be Zabiha. Please refer to “Zabiha” at the end of this chapter. The word “Halal” is a Quranic term and is used several times in different concepts. Some of them are related to foods. In this respect, Allah Swt says the following about halal foods in the Quran in Surah Al-Maidah (The Table Spread) [5: 87-88]
"You who believe! Forbid not the good things which Allah Swt made ‘lawful’ for you and transgress not. Lo! Allah Swt loves not transgressors. Eat of that which Allah Swt has bestowed on you as food ‘lawful’ and good and keep your duty to Allah Swt in Whom you are believers."