How do I install the OpenSSL libraries on Ubuntu?

I'm trying to build some code on Ubuntu 10.04 LTS that uses OpenSSL 1.0.0. When I run make, it invokes g++ with the "-lssl" option. The source includes: #include <openssl/bio.h> #include <openssl/buffer.h> #include <openssl/des.h> #include <openssl/evp.h> #include <openssl/pem.h> #include <openssl/rsa.h> I ran: $ sudo apt-get install openssl Reading package lists... Done Building dependency tree Reading state information... Done openssl is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded. But I guess the openssl package doesn't include the library. I get these errors on make: foo.cpp:21:25: error: openssl/bio.h: No such file or directory foo.cpp:22:28: error: openssl/buffer.h: No such file or directory foo.cpp:23:25: error: openssl/des.h: No such file or directory foo.cpp:24:25: error: openssl/evp.h: No such file or directory foo.cpp:25:25: error: openssl/pem.h: No such file or directory foo.cpp:26:25: error: openssl/rsa.h: No such file or directory How do I install the OpenSSL C++ library on Ubuntu 10.04 LTS? I did a `man g++` and (under "Options for Linking") for the -l option it states: " The linker searches a standard list of directories for the library..." and "The directories searched include several standard system directories..." What are those standard system directories?