What happens if I upgrade RAM?

I currently have a laptop that has 4GB of RAM. I would like to upgrade this to 8GB of RAM. What is the difference or what benefit do I use more memory in memory?

First of all: If your system only 32-bit can, it does not matter, because the RAM can still use only 4GB.

Benefits of larger memory are:

Better concurrent work with different programs
More power in a program, which has to cache a lot of data
Less stagnation and reloading of data-intensive stuff, because the memory is much faster than the paging file (this is used when the RAM is full).

Especially in gaming 8GB are standard today.

I rather ask the question why you want to upgrade if you do not even know why this should be good…

A friend said I should do the time, because my graphics card in his opinion ok. And the processor is also more in the green. The only hack would be at my memory.

Then you have more RAM.

If you have too little RAM (your RAM is often "full") your computer will multiply faster if you install more RAM, if you have "enough" RAM your computer will only run a little faster if you install more RAM, if you have enough RAM by far (~ 100GB) your computer will not get faster if you install more RAM.

Can have several programs open at the same time and in the background. As a simple example, you can have more tabs open in the browser without your PC jerky. Some programs also consume a lot of RAM for rendering such as games and graphics programs.

Whether you should upgrade it depends on what you use the laptop for and how good the rest of the laptop is because if you have a weak processor and an insufficient performance graphics card for your needs, you can also buy a new laptop or stand PC or assemble it yourself make someone do it for you.

You have to do that to upgrade:

Is Windows 64-bit? (32-bit can only address 3GB of memory.)
Check the website of the manufacturer for what you need for RAM. You have to see if you need DDR, DDR2, DDR3, DDR4. Caution: You need SO-DIMM modules.
Check if you can upgrade the RAM at all.
Build in the RAM Expansion Bar.