Dynamic Content Loading (Infinite Scroll)

So, I am building a website that has some photos on it (similar grid to Weheartit) and the main idea is that I will update those photos daily (I will put new photos on a daily bases). At first I wanted to make a pagination but then I realized that loading the content dynamically is a better idea. So, I wanted to load the content in a similar way like Weheartit (when user reaches the bottom of the page, new content is loaded and so on to infinity)... I am generally new to web design but I have a good knowledge of HTML and CSS and some base to mid knowledge on Javascript. So, I wondered if some of you could help me get on the right road of achieving my ideas. What do I need to learn to make this possible? Is it doable without PHP, do I need AJAX and so on... Thanks guys.