We have all used Adobe Acrobat Reader which is the industry standard for reading PDF Files. Many times, it is laggard to open and heavy to use.
SumatraPDFReader is extremely quick and opens up instantly. It is small, fast, customizable and free. Apart from PDF, it also supports various other file formats like eBook, comic book (cbz/cbr), DjVu, XPS, CHM, image formats and text documents for Windows.
The interface is minimalistic and apart from viewing the document, you could rotate it, resize it and even print it.
A very light and versatile PDF reader for day to day use.
On-lyneTech 