What It Is
The CPU (central processing unit) is the part of a server that does the thinking, running the code that builds each page. RAM (random access memory) is its working space, holding the information it needs right now. In a kitchen, the CPU is the cooks and the RAM is the counter space. More cooks work faster, and more counter space means more orders can be prepared at the same time.
Why It Matters for Your Business
When many people visit at once, or when a page needs heavy work, such as a store searching products or a booking system checking calendars, the server needs enough CPU and RAM to keep up. If it runs short, pages slow down or show errors. A gym running a membership sale might see its checkout freeze exactly when the most customers are trying to pay.
Good to Know
On shared hosting, CPU and RAM are shared and often quietly limited. On a VPS or cloud plan, they are listed as part of the plan, and you can usually add more. Before upgrading, check whether caching, a CDN or removing heavy plugins solves the problem, since those fixes are often cheaper than more hardware.