What is halal food? Why did most of the airlines (except a few in US) move to halal food catering in their flights?

Halal food is prepared in Islamic way and which is also hygienic way. To prepare halal meat (Mutton, Chicken) with Islamic ritual, the animal is slaughtered at throat to take out all blood from the body (some harmful element may be in blood). So, Halal meat is prepared in hygienic way and is good for all people

 The concept of Halal Food was limited to Muslim only. As I recall, the concept of Halal food was globally introduced and commercialized by Malaysian Airlines in mid- and the market saw a huge demand. In the mid-, the demand for Halal meat quickly reached USD <1.5> billion and now the market size is more than USD<> billion per year

 Market Expansion: To capture the Muslim air travelers market segment, Initially, Malaysian Airlines expanded quickly to Middle East and Europe and USA and started popularizing Halal food in order to capture the market and it worked nicely.

 With huge growth of Muslim travelers from Middle East and Asia, all Airlines of Asia and Europe have switched to Halal Food now (no airlines serve pork now except few in US).  I hope everyone would Love to see the signboard inside the Aircraft “We serve only Halal Food”.

It's very important that we are careful about what we eat and always make sure that we eat Halal food. Haram food is not only pork, but also cow or sheep or chicken which have not been slaughtered in a proper Islamic way. 

Any cow, sheep or chicken which has not been properly slaughtered in an Islamic way is Haram to eat. They are called "Maytah" (dead animal). For example, some chicken slaughter houses hang chicken by their legs on a long slaughtering machine and they dip the chicken in water and / or electrify them. Those chicken are considered "Maytah" and we're not allowed to eat them. 

Also, in some chicken slaughter houses they again hang many chicken in a row by their legs and then a person presses a button and the chicken are carried in this lined and a blade automatically beheads them when they reach a certain point. Those chicken are also considered "Maytah" and we're not allowed to eat them.

In some slaughter houses they shoot the cows with a gun in their head. The cows (or sheep) who die this way are considered "Maytah" and we're not allowed to eat them. 

So Muslims must be careful about what they eat and investigate to the best of their abilities if the meat or chicken they are about eat were slaughtered properly or not before they eat it. 

It is a particular way in which the meat is prepared. The importance is specially for the muslim religion as they can have only halal meat.These airlines are serving halal food to increase their consumer base basically.

A good answer given by Mr.Md. Fazlur Rahman . Thank you 

to serve muslim person

halal food it is prepare by islamic way before cooking