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Our digital devices contain lots of information.

This information includes:

• instructions that our devices need to work properly
• software applications that we use on our devices
• digital content that we have created like photos or videos

When we open an app to view a photo we have taken, or listen to our favourite song, the computer gets the information that has been stored in its memory.

A computer's memory is where it stores the information that we can use.

The information is stored in the form of 1s and 0s. This is called binary.

Binary is a system for representing numbers that uses the digits 0 and 1.

It is a base two system because it only uses two digits.

The number system that we use every day, is known as a base 10 system.

It uses ten digits (0,1, 2, 3, 4, 5, 6, 7, 8, 9).

We have lots of information stored on our digital devices that isn't in the form of numbers, such as:

• music that we listen to
• games that we play
• homework we have written

When we save this information on our digital device, it is changed from music, images and words into binary code so that it can be stored on the device.

It is given a file name which gives our digital device information on what type of file it is and which application should be used to open this file.

There are many different types of files. Some of the most common are:

When we want to open the file, the application changes the information which has been stored as binary, back into information we can understand on our digital devices like music, words and pictures.

We never see the binary code at all.

Computers, laptops and tablets store our information in their memory.

A digital device may have memory that is:

• inside the device
• on a removable storage device
• in the cloud

There is memory inside the computer called RAM (random access memory).

RAM is used to store data for the programs that are running.

This information is only stored whilst the device is turned on.

When the device is turned off the information is lost.

We can save information to internal or external hard drives or on a memory stick which we normally plug into our devices.

This information is not lost when we turn off our computers.

We can transfer files from one device to another using a memory stick.

Some people choose to store information in the cloud. The cloud is a special computer that has a very big memory. It can store lots of people's files.

When we have stored information in the cloud, we can access it from anywhere in the world as long as we have an internet connection.