The Megabyte is the equivalent of 1024 kilobytes or 1,048,576 bytes. However, the International Measurement System argues that the mega prefix should be used to mean one million. So as not to deceive customers, hard disk manufacturers and other storage devices have begun using this recommendation, and equating the megabyte to 1,000,000 bytes. This allowed to reduce the number of clients, who complained, claiming that their devices had less capacity than the one that was advertised. In the early days of computing, a megabyte was considered a lot of data, nowadays, it is not so. A megabyte lets you store a small book, 100 megabytes allow you to store multiple volumes of one encyclopedia, and 640 megabytes is the space occupied by a music CD.
The Byte is a digital information unit equivalent to eight bits. Each byte represents a single text character on a computer. A byte can represent a letter, a symbol, a number or a punctuation mark. The byte is used to specify the size or amount of memory or the storage capacity of a device. Some programming languages use the term byte to represent an integer-type variable, which takes up less space than other similar numeric variables. Something similar also occurs in the vast majority of databases. Because storage space is very important, sometimes when you want to store an integer, you should get an idea of the size of that number. For example, if we want to store the age of a person we will not need such large numbers as to save the balance of our bank account, which in some cases can reach several digits.