How to understand Meltdown and Spectre

For those interested in the recent Meltdown and Spectre vulnerabilities, this article provides a very nice high level overview.

High level description of Meltdown and Spectre:

• Meltdown: can be used by an attacker to read memory from other processes without having the required privileges.
• Spectre: takes advantage of speculative execution to allow an attacker to potentially gain access to sensitive data in a program.