How can I convert bitcoins to tangible cash in hand?

Bitcoin is a cryptocurrency invented in 2008 by an unknown person or group of people using the name Satoshi Nakamoto and started in 2009 when its implementation was released as open-source software.

Bitcoin was born out of discontentment with traditional (central) banking, monetary, credit, and transaction systems. That's why there is no central institution or authority behind Bitcoin that can administer you. How much one bitcoin is worth is entirely decided by free-market dynamics within the community. That's possible because the supply of bitcoins is held artificially scarce.

It's a currency from the people for the people. If you and your community want to build an economy upon it, you all can get some GPUs or FPGAs and start mining. It will be entirely up to initiatives in your community to build services that exchange to and from traditional (Libyan) currencies, to offer goods and services, or to manufacture physical coins similar to Casascius to put into circulation (although these are rather seen as a gimmick, it may be much more convenient to use mobile phone clients nowadays for meatspace trading). Even in the US and Europe where it's most popular, Bitcoin is still in its infancy and this process is only just happening.

Visit here to exchange cryptocurrency, zcash to paypal

If you happen to find Bitcoin inadequate to build a local economy upon, because you can't mine enough or you'd have to invest too much to buy some, you may take a look at different concepts like Ripple et al. These concepts build upon trust relationships however, you'll lose some of the features like the global scope and the (relative) anonymity/pseudonymity that Bitcoin offers. Money is a tool to transfer value after all. There are currently no known tools or technologies that can solve all problems at once if you don't want a currency that is enforced by an authority.