Historically, the development side and the operations side of software development have worked separately, often at odds with each other. This led to a low production level. It is the job of developers to release products, updates and fix bugs in live products. It is the operations job to ensure and maintain uptime in production.
As a result, developers have encouraged changed and operations have resisted it. When changes would be deployed it would cause problems for operations. New code would have to be massaged, often quite a bit, to prevent errors or down time. As a result, deployments of new code would be few and far between. Production would be slow and changes and improvements to existing products would be equally as sluggish. This is would end up costing companies time and money.
There is a solution to this frustration called DevOps. DevOps is centered around Development teams and Operations teams working together with DevOps tools. These tools will automate problems and ensure that everyone is working in environments that are identical. Smaller chunks of code are written, tested and then deployed at a much faster rate. This saves businesses a lot of time and money. Operations and development teams are collaborating together and testing their code more often. This results in little to no down time after deployments.
DevOps is focused on a collaboration mentality and the tools that assist this collaboration to be executed seamlessly.