按照官方的說法：Cairo is a vector graphics LIBRARY with cross-device output support.
翻譯過來，就是cairo是一個支持多種輸出的向量圖形庫。
具體解釋一下，也就是說，cairo是種畫圖的工具庫，他可以向多種設備上畫圖，比如：
cairo可以輸出到png,可以輸出到pdf，可以輸出到ps，可以輸出到xlib，可以輸出到XCB，可以輸出到win32，以后還要輸出到svg
我們可以展望一下，如果cairo能夠統一linux下所有的畫圖接口，那么，所見所得可能就會成為顯示。
The Intel® JPEG LIBRARY provides a set of highly optimized C functions that implement JPEG compression and decompression on Intel architecture processors
The Spectral Toolkit is a C++ spectral transform LIBRARY written by Rodney James and Chuck Panaccione while at the National Center for Atmospheric Research between 2002 and 2005. The LIBRARY contains a functional subset of FFTPACK and SPHEREPACK, including real and complex FFTs in 1-3 dimensions, and a spherical harmonic transform. Multithreading is supported through POSIX threads for the multidimensional transforms. This reference guide provides details of the public interface as well as the internal implementation of the LIBRARY.
