Google's Chrome DevTools offers a convenient Terminal option for you if you use the Chrome browser in OS X.
Topher KesslerMacFixIt Editor
Topher, an avid Mac user for the past 15 years, has been a contributing author to MacFixIt since the spring of 2008. One of his passions is troubleshooting Mac problems and making the best use of Macs and Apple hardware at home and in the workplace.
To install it, simply go to the DevTools Terminal application page within Chrome, and click the link to install the Terminal add-on. When done, it will appear as an app that you can click to load, and the current tab will turn into a Terminal window, bringing you to the familiar command prompt in your home directory.
As with all Chrome apps, you can set some options for how the program is displayed by right-clicking on it and choosing either to open as a regular tab (the default), as a pinned tab, or in full screen. You can open as many instances of the DevTools Terminal as you can browser tabs, which makes it a convenient tabbed-terminal option to use as well. For example, if you are performing some task in Terminal and wish to look up how to perform some command, you can make a new tab, browse the Web for instructions, and then go back to Terminal to complete the task.
Given that your Mac's Terminal app also supports tabs and multiple windows, among other options, the DevTools Terminal may seem redundant; however, as with any important application, it may be beneficial to double-up on functionality. For example, take Web browsing: if you only have Safari on your system ,and some unknown problem is preventing it from opening, then you will not have access to the Web. Therefore, it's recommended you keep at least one other browser on your system, even if you do not regularly use it. Similarly, having multiple Terminals could allow you to perform commands in case one not is not working.