What are Pixels:
Pixels are smallest unit of information that is found in a digital photo. These tiny bits of picture elements all together form the digital photo. Your digital photo is measured by “X” amount of pixels high by “Y” amount of pixels wide. When you multiply the “X” axis times the “Y” axis you get the total amount of pixels contained in your photo. This is where the term Megapixel comes from when describing a digital camera. It is the amount of total possible pixels. Measured in millions, taken in a photo taken from that digital camera.
An image from a 10 Megapixel camera contains 2,593 pixels high and 3,888 wide. This multiplies to 10, 077,696 pixels, thus the 10 megapixels.
Resolution is the amount of pixels in an inch. Measured as pixels per inch (ppi) it can differ depending on the final size of the image. The pixel dimension remains the same, meaning you have X amount of pixels high by Y amount of pixels wide, but the resolution changes when the image size goes up or down,