what is sdram?

[Lilninjsways]

I have seen ddr4 ram and it says sdram what is that?

[BloodyWaters]

It's just ram. Normal ram. 

[JPotze]

it means it is synchronous dynamic random access memory.

[Nick V]

At first we had RAM, a type of it was Dynamic RAM. Then the Synchronous Dynamic RAM came and we had SDRAM.
(Then Intel came with RDRAM but very few played with it and was out of the market.)
But SDRAM was Single Data Rate. So we double it and we got Double Data Rate SDRAM or DDR SDRAM.
Then we decided to stop adding acronyms and we put a number and we got DDR2 SDRAM.
And the story went on... 

[typographie]

45 minutes ago, Lilninjsways said:

I have seen ddr4 ram and it says sdram what is that?

Basically it's just a more specific and technical name than "RAM." The type of memory we use in most mainstream PCs is SDRAM.

 

https://en.wikipedia.org/wiki/Synchronous_dynamic_random-access_memory

[rjfaber91]

4 hours ago, Lilninjsways said:

I have seen ddr4 ram and it says sdram what is that?

DDR4 is not the full name, it's just the one we use because it's short and convenient. The full name is Double Data Rate Fourth Generation Synchronous Dynamic Random Access Memory, or DDR4SDRAM for "short". Quite a mouthful, you'll agree, so it's customary to leave the SDRAM bit out.