1) The development of blockchain technology, first introduced in 2008 with the creation of Bitcoin, has enabled secure and decentralized digital transactions and led to the emergence of cryptocurrencies.

2) Mount Kilimanjaro in Tanzania is the highest mountain in Africa and attracts climbers from around the world.

3) The impact of social media platforms on society and politics has been a subject of debate, including concerns about misinformation, privacy, online harassment, and the influence of these platforms on public opinion and democratic processes.

4) The first commercially successful video game was "Pong," released in 1972 by Atari.