A market order is an instruction to buy or sell a share at the best available price in the market. This means that the order will be executed immediately at the current market price, regardless of the price level.

A buy limit order, on the other hand, is an instruction to buy a share at a specific price or lower. The order will only be executed if the market price falls to the specified price or lower. The buy limit order is used to ensure that the investor does not pay more than a certain price for the share.
​

In summary, the main difference between a market order and a buy limit order is that a market order is executed immediately at the current market price, while a buy limit order is executed only if the market price falls to the specified price or lower.