If you want to prevent your children from using any particular websites or your employee to be away from unnecessary websites, URL or Apps then there are some ways through which you can prevent them from using the web or app. To do so, you can configure Safari, set Parental Lock or there are some apps available for blocking websites. We have explained all three methods (block on Safari, Parental Lock and Lock through app) to block website on safari.
How to Block Websites in Safari Running Mac OS X Yosemite
Step #1. Launch the Terminal (Open Spotlight and search for the Terminal).
Step #2. In the Terminal type
sudo pico /etc/hosts and press Enter. Pressing enter, you will be asked to enter the Administrator Password
Step #3. Once you enter Password, the Terminal text program will open on the host file. Scroll the cursor down to the bottom and press Enter. It will create a new line to type.
Step #4. Type the IP
127.0.0.1 followed by the URL or Site address.
i.e: 127.0.0.1 www.yahoo.com. And press Enter. Type another URL or Site following the same steps. Do not add more than one URL or Site in a single line, each entry should be in a separate line.
Step #5. Once you are done with the entry (the sites or URL, you want to block), press Ctrl+O and then Enter to save them and exit the editor.
Step #6. Then Flush your cache in order to take effect to the settings, type
sudo dscacheutil -flushcache to flush your DNS and press Enter.
Now open the URLs or Sites you have blocked. If it is set up correctly you should not be able to open website/URL.
How to Unblock URLs or Websites you Have Blocked:
Launch Terminal → type sudo pico /etc/hosts → remove the URL and Site → press Ctrl+O and Enter
How to Block Website/URL on Mac with Parental Controls:
Step #1. First of all make a separate User Account for your children.
Step #2. Then go to System Preferences on your Mac.
Step #3. Click on Parental Controls.
Step #4. Then click on the lock icon (shown at the bottom of the window.)
Step #5. Clicking on the lock icon, you will be asked to enter password. Click to unlock.
Step #6. Then select the User account that you want to lock.
Step #7. Select Web tab.
Step #8. Then select Try to limit adult websites automatically.
Step #9. Click on Customize…
Step #10. Under Never allow these websites, click on “+” icon and enter URLs/websites that you want to block.
After adding the websites or URL you can be sure that it cannot be accessed by the banned user.
Block Website on Mac OS X Yosemite Through App
There is an app, called Self Control, an open source application for Mac OS X. Through the app you can block the websites, URL, mail, and so on. The best thing about the app is when you block the sites/mail/URL, you cannot access the blocked sites unless and until the date you have added gets expired.
To Block, set a period of time and add sites to the blacklist and click Start. Once you click on start,it will be blocked for the period of time you have set. Until the timer expires, you cannot access those sites even if you delete the app.