Error with Webkit Build Procedure

Hi everybody,

I am new to Linux. I downloaded the WebKit source code from here. I am building the source code with help of this.

After executing below command, i got errors related to glib-2.31.2.
./autogen.sh --prefix=/usr
I solved those errors and again issued above command. I got below errors.

checking for ZLIB... configure: error: Package requirements (zlib) were not met:

No package 'zlib' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables ZLIB_CFLAGS
and ZLIB_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

I searched in many forums for this problem, but no use. Please help me regarding this. Thanks