Is my CPU will fit any socket Intel motherboard?

Dual Core 1.8 Ghz I have and I want to buy new Intel processors. 1.Will fits my CPU in any decision or are of different sizes: 775 1156 1366 2.Do I have to buy specific processor for the specific motherboard?

Processors are made for specific shots. You can not mix and match. Intel LGA1156 is the new series of processors i (i5, i7). LGA1366 appears to be new for the upcoming i7 processors Core. 775 is the most common is for Pentium 4, Pentium D Dual-Core, Core 2 Duo, Core 2 Quad, Core 2 Extreme, et al. I need to know the exact model of your processor is OK to say precisely what type motherboard you need, but I bet you want a motherboard 775. Be absolutely certain, however.