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It is not increasing physical memory at all. Its purpose is something else entirely. What it can do is make available other backing stores that allow programs to use more memory than is physically available.

Virtual memory is used to separate and isolate processes from each other and also allow memory access to be diverted to alternative locations.

Virtual memory allows the system to give every process its own memory space isolated from other processes. With programs effectively operating in their own space it gives them full access to the entire address space rather than having to work around other programs which might also need to use the "same" addresses. This has the side effect of increasing reliability and security as processes cannot easily interfere with each other.

The virtual memory space of an application is built up as needed. An application looks (to itself) to be in a single contiguous block of memory but could actually be completely scattered across physical memory.

Virtual memory also allows memory accesses to be trapped and diverted which allows us to use features like a swap file. What this means is that we can push parts of memory that haven't recently been used out to disk and set up a pointer that says "this block of memory is in file x at location y" and then we can free up the physical memory area for use by another application. When an application needs that memory it can be read back from disk, placed at some location of physical RAM (potentially different from where it was before) and mapped back into the same location of virtual memory as it was previously.

Using these techniques we improve the stability of the system and allow more processes to run in a confined space without them unduly affecting each other. It does not "increase memory", but instead allows us to more effectively use what we have.

The swap file is enabled by virtual memory systems, but in the past was confused as being the virtual memory.

It is not increasing physical memory at all. Its purpose is something else entirely. What it can do is make available other backing stores that allow programs to use more memory than is physically available.

Virtual memory is used to separate and isolate processes from each other and also allow memory access to be diverted to alternative locations.

Virtual memory allows the system to give every process its own memory space isolated from other processes. With programs effectively operating in their own space it gives them full access to the entire address space rather than having to work around other programs which might also need to use the "same" addresses. This has the side effect of increasing reliability and security as processes cannot easily interfere with each other.

The virtual memory space of an application is built up as needed. An application looks (to itself) to be in a single contiguous block of memory but could actually be completely scattered across physical memory.

Virtual memory also allows memory accesses to be trapped and diverted which allows us to use features like a swap file. What this means is that we can push parts of memory that haven't recently been used out to disk and set up a pointer that says "this block of memory is in file x at location y" and then we can free up the physical memory area for use by another application. When an application needs that memory it can be read back from disk, placed at some location of physical RAM (potentially different from where it was before) and mapped back into the same location of virtual memory as it was previously.

In the same way as the page file is used virtual memory can also allow the operating system to do what is effectively "lazy" loading of shared libraries for a program. When the main program tells the operating system that it wants to use a particular library then the operating system can save time by checking the requirements for the library, allocating the space in the virtual memory area for the application, but rather than load the entire library in it can defer loading pages of the library in from disk until they are actually needed. In this way the only parts of the library that get loaded into RAM are the parts that are actually used by the program, parts that are never used never get loaded and so don't waste RAM.

Using these techniques we improve the stability of the system and allow more processes to run in a confined space without them unduly affecting each other. It does not "increase memory", but instead allows us to more effectively use what we have.

The swap file is enabled by virtual memory systems, but in the past was confused as being the virtual memory.

It is not increasing memory at all. Its purpose is something else entirely.

Virtual memory is used to separate and isolate processes from each other and also allow memory access to be diverted to alternative locations.

Virtual memory allows the system to give every process its own memory space isolated from other processes. With programs effectively operating in their own space it gives them full access to the entire address space rather than having to work around other programs which might also need to use the "same" addresses. This has the side effect of increasing reliability and security as processes cannot easily interfere with each other.

The virtual memory space of an application is built up as needed. An application looks (to itself) to be in a single contiguous block of memory but could actually be completely scattered across physical memory.

Virtual memory also allows memory accesses to be trapped and diverted which allows us to use features like a swap file. What this means is that we can push parts of memory that haven't recently been used out to disk and set up a pointer that says "this block of memory is in file x at location y" and then we can free up the physical memory area for use by another application. When an application needs that memory it can be read back from disk, placed at some location of physical RAM (potentially different from where it was before) and mapped back into the same location of virtual memory as it was previously.

Using these techniques we improve the stability of the system and allow more processes to run in a confined space without them unduly affecting each other. It does not "increase memory", but instead allows us to more effectively use what we have.

The swap file is enabled by virtual memory systems, but in the past was confused as being the virtual memory.

It is not increasing physical memory at all. Its purpose is something else entirely. What it can do is make available other backing stores that allow programs to use more memory than is physically available.

Virtual memory is used to separate and isolate processes from each other and also allow memory access to be diverted to alternative locations.

Virtual memory allows the system to give every process its own memory space isolated from other processes. With programs effectively operating in their own space it gives them full access to the entire address space rather than having to work around other programs which might also need to use the "same" addresses. This has the side effect of increasing reliability and security as processes cannot easily interfere with each other.

The virtual memory space of an application is built up as needed. An application looks (to itself) to be in a single contiguous block of memory but could actually be completely scattered across physical memory.

Virtual memory also allows memory accesses to be trapped and diverted which allows us to use features like a swap file. What this means is that we can push parts of memory that haven't recently been used out to disk and set up a pointer that says "this block of memory is in file x at location y" and then we can free up the physical memory area for use by another application. When an application needs that memory it can be read back from disk, placed at some location of physical RAM (potentially different from where it was before) and mapped back into the same location of virtual memory as it was previously.

Using these techniques we improve the stability of the system and allow more processes to run in a confined space without them unduly affecting each other. It does not "increase memory", but instead allows us to more effectively use what we have.

The swap file is enabled by virtual memory systems, but in the past was confused as being the virtual memory.

It is not increasing memory at all. Its purpose is something else entirely.

Virtual memory is used to separate and isolate processes from each other and also allow memory access to be diverted to alternative locations.

Virtual memory allows the system to give every process its own memory space isolated from other processes. With programs effectively operating in their own space it gives them full access to the entire address space rather than having to work around other programs which might also need to use the "same" addresses. This has the side effect of increasing reliability and security as processes cannot easily interfere with each other.

The virtual memory space of an application is built up as needed. An application looks (to itself) to be in a single contiguous block of memory but could actually be completely scattered across physical memory.

Virtual memory also allows memory accesses to be trapped and diverted which allows us to use features like a swap file. What this means is that we can push parts of memory that haven't recently been used out to disk and set up a pointer that says "this block of memory is in file x at location y" and then we can free up the physical memory area for use by another application. When an application needs that memory it can be read back from disk, placed at some location of physical RAM (potentially different from where it was before) and mapped back into the same location of virtual memory as it was previously.

Using these techniques we improve the stability of the system and allow more processes to run in a confined space without them unduly affecting each other. It does not "increase memory", but instead allows us to more effectively use what we have.

The swap file is enabled by virtual memory systems, but in the past was confused as being the virtual memory.

It is not increasing memory at all. Its purpose is something else entirely.

Virtual memory is used to separate and isolate processes from each other and also allow memory access to be diverted to alternative locations.

Virtual memory allows the system to give every process its own memory space isolated from other processes. With programs effectively operating in their own space it gives them full access to the entire address space rather than having to work around other programs which might also need to use the "same" addresses. This has the side effect of increasing reliability and security as processes cannot easily interfere with each other.

The virtual memory space of an application is built up as needed. An application looks (to itself) to be in a single contiguous block of memory but could actually be completely scattered across physical memory.

Virtual memory also allows memory accesses to be trapped and diverted which allows us to use features like a swap file. What this means is that we can push parts of memory that haven't recently been used out to disk and set up a pointer that says "this block of memory is in file x at location y" and then we can free up the physical memory area for use by another application. When an application needs that memory it can be read back from disk, placed at some location of physical RAM (potentially different from where it was before) and mapped back into the same location of virtual memory as it was previously.

Using these techniques we improve the stability of the system and allow more processes to run in a confined space without them unduly affecting each other. It does not "increase memory", but instead allows us to more effectively use what we have.

The swap file is enabled by virtual memory systems, but in the past was confused as being the virtual memory.