How should daily personal data and photos be stored?

Today, I heard another friend crying that all the photos in the SLR camera were lost. I feel sorry that it is necessary to write an article to share my experience and lessons with you.

At present, most memory cards, USB flash drives and mobile hard disks on the market have different storage principles, but all of them can keep data from being lost after power failure, thus achieving the purpose of long-term storage. So why do I say they are unreliable? First of all, these electronic storage devices will be damaged by external forces. Once the U disk or hard disk is squeezed, the heat is too high, or immersed in water, these will lead to internal damage of the equipment. These damages are usually called compulsory physical damages, which are irreversible and irreparable. But in most cases, my friend's storage device is inexplicably broken, even if it is used normally in the morning, it can't be fully opened in the afternoon. For this kind of non-physical damage, I think we can start with their storage principle.

? The storage principle of memory card and USB flash drive is similar:

? -Non-science majors skip this paragraph.

? A floating gate for storing electrons is formed on a semiconductor with unidirectional current conduction between the source and the drain. The floating gate is wrapped by a silicon oxide film insulator. Above it is a select/control gate that controls the conduction current between the source and the drain. Whether the data is 0 or 1 depends on whether there are electrons in the floating gate formed on the silicon substrate. One electron is 0, and none is 1. Flash memory, as its name implies, deletes data for initialization before writing. Specifically, electrons are extracted from all floating gates. Some data will return to "1". Write only when the data is 0, and do nothing when the data is 1 When writing 0, a high voltage is applied to the gate electrode and the drain electrode, increasing the electron energy conducted between the source electrode and the drain electrode. In this way, electrons will break through the oxide film insulator and enter the floating gate. When reading data, a certain voltage is applied to the gate electrode, the current is 1, and the current is 0 if it is small. When there are no electrons in the floating gate (data is 1), when a voltage is applied to the gate electrode, a voltage is applied to the drain, and a current will be generated between the source and the drain due to the movement of a large number of electrons. But when there are electrons in the floating gate (data is 0), the electrons conducted in the channel will decrease. Because the voltage applied to the gate electrode is absorbed by the floating gate electrons, it is difficult to affect the channel.

Because the computer only knows 0 and 1, figuratively speaking, a person is in a room. If it is 0, people will go in, and when it reaches 1, people will stand outside. When reading a book, you only need to look at the replies from several people in the corridor to find out whether there is anyone at the door of the room (0 10 1). This sort order will lead to the result of data, and then,

The storage principle of hard disk is very different from that of U disk:

When we turn on the computer, we can hear the buzzing inside the chassis. One of the sources of this sound is the rotation of the fan, and the other is the sound generated by the rotation of the disk inside the hard disk. Magnets have two polarities, one is South Pole (S Pole) and the other is North Pole (N Pole). Those magnetic particles on the surface of the disk (disk) in the hard disk are magnetic particles. The disk is divided into several concentric circles (called tracks), and countless small magnets are randomly arranged on each concentric circle track. When these small magnets are influenced by the magnetic field from the magnetic head, the arrangement direction changes accordingly. Unifying the direction of the small magnet in a certain area with the magnetic force of the magnetic head can make the magnetic field in this area have the same polarity. If the two polarities of S/N correspond to 0 and 1 in binary, it can represent binary data. These magnetic particles are permanent magnets. Even if the magnetic head is absent, it can keep its polarity for a long time, thus achieving the purpose of storing information. When reading data, the magnetic head can sense the different polarities of magnetic particles and convert them into different electric pulse signals. These original signals are translated by the decoder into data that can be used by the computer.

Generally speaking, there are more than n small magnets on the disk, with the positive pole indicating 1 and the negative pole indicating 0. When the magnetic head does induction, you can know the number represented by each magnet on the disk, and then you can get the data after arrangement.

? If you want to make the magnet lose its magnetism, you can use a stronger magnet to attract it, or you can throw the magnet hard to disturb its internal magnetic field. So is the hard drive. Any large vibration and magnetic field will interfere with the data on the hard disk. Some computers accidentally dun when using, and the screen will be blank. This is the standard hard disk vibration damage. So in theory, the hard disk is more easily damaged than the U disk, but in most cases, the hard disk is damaged.

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? Suggestion: If you need to store a lot of things, dozens of G's and hundreds of G's, you'd better use a computer to store them. Don't buy a USB flash drive above16 g. Remember that USB flash drives and memory cards are only data transmission tools, and cannot be used as long-term storage objects of data, such as taking pictures for a period of time. Get on the hard disk in time and make sure that there is data backup in the memory card or USB flash drive, even if your memory card or USB flash drive is lost or infected outside. There won't be much loss. If there are many photos and take up a lot of hard disk space, I recommend using cloud disk to store photos, which will greatly reduce the chance of loss. Both 360 Cloud and Baidu Cloud are doing several tasks. You can give a few T's of capacity by tying up your mobile phone.

? That's about it. It's all a lesson of blood. These data are priceless. Just look at my suggestion. I think most of the data can be avoided. Good luck.

? Ps: A friend of a photographer said that he usually uses two hard disks to back up photos, which is really expensive. After reading my article, he said he would consider getting it into the cloud disk. ...