Ram a volatile memory

[GSquadron]

I was reading a book about computers and it explained that ram is a volatile memory.
It was written that "usually" it is a volatile type of memory used for temporary storage.

Can anyone explain what are the other usages of ram?

 

[Frick]

NVRAM for instance. Flash memory is that.

 

[_JP_]

There's RAM and there's ROM.
RAM = Volatile -> Power-off = Data gone.
ROM = Not volatile -> Power-off = Data still there.
You must have missed something. RAM, in it's usual definition, is tied to primary memory and, unless I'm forgetting some obscure incarnation, it has always been volatile.

EDIT: Yes, there's NVRAM, but ROMs (for example) are NVRAM.

 

[Beertintedgoggles]

RAM = Random Access Memory
ROM = Read Only Memory

Most ROM is also considered to be RAM. Just because we use the term RAM to always mean system memory doesn't mean that is the only or even the correct definition.

 

[W1zzard]

a volatile memory is memory that loses its contents on some condition (usually power off)

if you had a pc with non volatile ram you'd just turn it off (without hibernation or standby) and it would be back where you left it when turned on.

the reason we dont have this is because dram is the fastest cheapest memory available

 

[Frick]

There's RAM and there's ROM.
RAM = Volatile -> Power-off = Data gone.
ROM = Not volatile -> Power-off = Data still there.
You must have missed something. RAM, in it's usual definition, is tied to primary memory and, unless I'm forgetting some obscure incarnation, it has always been volatile.

EDIT: Yes, there's NVRAM, but ROMs (for example) are NVRAM.

ROM = Read Only Memory. It stays there but it's not very write friendly. Firmware etc is often written on these. ROM and NVRAM are different, but they're both non volatile.

 

[GSquadron]

Why ram is considered as primary storage (main memory to be precise)?
Because of speed? Or because it is near the cpu? Or by its construction?

 

[W1zzard]

you need some kind of storage for data. you could build a computer that operates without dram, using a hdd only, but it would be very very very slow.

good read that might help you get some answers:
http://en.wikipedia.org/wiki/Von_Neumann_architecture

 

[Frick]

Why ram is considered as primary storage (main memory to be precise)?
Because of speed? Or because it is near the cpu? Or by its construction?

It's not storage, it's memory. Storage is harddrives, optical discs etc.

It's a buffer between the CPU and the storage. You have CPU - level 1 cache (very very quick) - level 2 cache (slower but still quick) - moar cache if present - DRAM (pretty fast still) - storage.

So it's because of all of those things. It's fast, it's near the CPU and the construction makes it "simple" and pretty quick.

 

[Jstn7477]

Why ram is considered as primary storage (main memory to be precise)?
Because of speed? Or because it is near the cpu? Or by its construction?

Programs/data must be loaded into RAM for execution or manipulation by the CPU.

 

[D4S4]

not obligatorily (i thought i just made up a word but spellchecker says it's fine), but in order to execute as fast as possible.