Cover order market price execution


Doubt 1.When if we buy cover order it will be executed in market price.So when we place cover order why it say trigger pending or why it not get executed within second just like normal market order as it is market order.If you are saying stop loss so say stock A trading at 100 and stop loss is of 98,so why it not get instant execution.

Doubt 2.Secondly,it is known cover order is only market order but i came various sources wher eit says it can limit order.So why is this partiality?Check some website where i come this:

Even there is video demonstration of cover order with limit price:

Also,i have lot of websites.Please reply fast.