What It Is That Makes The Memory Ram?

RAM is an abbreviation of Random Access Memory which is a type of data storage used in computers. It permits data to be retrieved  in any order and without the physical movement of the storage medium. This type of memory allows data to be returned at a constant time and speed regardless of its actual location. This contrasts with storage mechanisms such as discs and tapes which rely on the physical movement of the recording medium or storage head.

Modern computers can hold up to 2GB of RAM which is enough to sustain both multi-tasking as well as heavy graphic applications. Most types of RAM are volatile, which means they lose all data when the computer is powered off. However, if an external power source is connected, the volatile memory can retain its data after the computer is shut down.     

Short retrieval time is one of the key benefits of RAM. Because of this speed and consistency, RAM is used for loading, displaying and manipulating applications and data. In most personal computers, RAM comes in an easily upgradeable form called memory sticks that can be easily removed and replaced. A small random access memory, referred to as "cache memory" is integrated with the CPU.

You've asked two questions. Your one question is what does a RAM memory means. And your second question is about pop-up windows. We must see them turn by turn. Then we can develop a good understanding of it.
In computers there are 2 kinds of memories used. One is called ROM, which stands for "Read Only Memory" and second type is called RAM, which stands for Random-access memory. So from its name you can easily perceive what does it mean? The RAM is a memory in a computer which can be accessed at any time. Or you can say RAM is a memory device in which information can be accessed in any order. And the different kinds of computer buses make these types of memories. Now you must know what does a bus means in computer. A bus is a circuit that connects different components of computer and allows information to transfer as electronic impulses. Those the memory buses make the RAM to work.
As far as pop-up windows are concerned, it means if you open some windows or some web sites some windows automatically emerge quickly. Those windows are called pop-up windows. I hope, it is clear now.