Intel CPU Ranges
-Core - this is Intel's flagship desktop and mobile CPU series. The earliest models (Core Solo and Core Duo ) were laptop-only chips. The Core 2 series introduced desktop versions plus 64-bit and multi-core support. The current range is divided into Core i3, i5, and i7 brands, with i7 representing the best performing models. The Core i range has been based on three microarchitecture, codenamed Nehalem, Sandy Bridge, and lvy Bridge.
-Pentium - the Pentium used to be Intel's premium 32-bit CPU brand and you may still find Pentium 4-based computers in use. The Pentium brand has been reintroduced to represent "mid-range" CPU models based on the Nehalem and Sandy Bridge microarchitecture.
-Celeron - this gas long been Intel's budget brand.
-Atom - this is a relatively new (2008) brand designating chips designed for low-power portable devices (smartphones and tablets).
-Xeon - this brand is aimed at the server / workstation market. Current Xeons are often differentiated from their Core i counterparts by supporting n-way multiprocessing and ECC memory and coming with larger caches.
AMD CPU Rangers
-Athlon - this was AMD's long-standing premium consumer brand. Modern Athlons start with the Athlon 64 and its FX (top-end) and X2 (dual-core) variants. With the reintroduction of the plain "Athlon" series and subsequent Athlon 2 models, the brand has been repositioned for the midrange market.
-Phenom - this replaced the Athlon as AMD's premium CPU brand. The latest range is branded Phenom 2.
-Sempron - AMD's budget brand, positioned to compete with Intel's Celeron.
-Turion - this brand is used to for laptop processors.
The brands above are likely to be phased out over the next few years, with the following brands replacing them:
-AMD Fusion (A series) - this represents what AMD calls Accelerated Processing Units (APU), which basically combine a CPU and GPU (Graphics Processing Unit)80. At the time of writing, the line-up is divided into A4 (mid-range), A6 and A8 (high-performance).
-AMD FX - this brand now represents AMD's pitch for the high-end "enthusiast" segment.
-Opteron - AMD's long-standling version of the Xeon brand, aimed at the server - workstation market.