When it comes to the creation, sharing and storage of documents (files, notes, pictures..etc), there are two programs that step out from the others on the Internet!
Evernote and Dropbox are both available as a client software to be installed on a PC/Terminal and as web services (via a browser).
Dropbox is primarily used for storage and synchronization of your documents between your devices (computers, smartphones, tablet computers). This is an online storage solution, which offers 2GB of free storage (expandable to 8 GB via a refferal program), and up to 50 or 100 GB for paid versions.
Evernote, it is a program for taking notes everywhere and on any support (from your mobile phone, tablet or computer). It supports audio formats, images, texts (although videos are not supported, it can store a livestream recording from a webcam) that you can insert into your notes. You can then share your notes with your contacts or via social networks.
Dropbox requires the installation of a downloadable client software: here.
This client is available for Windows, Mac, Linux and mobile devices running iOS (iPhone, iPad), Android and Blackberry OS.
Once installed, you will need to create an online account to be able to access the Dropbox system. Your username will be your e-mail address.
Once created, your account gives you access to the online interface and access your personal files from your computer.
Evernote does not work on the same principle as Dropbox:
Though its primary purpose is to store documents online, you can't save files as they are, instead you need to create notes (a creative association of ideas around a particular theme) using images, text , audio ..etc
You will need to install the Evernote client software on your computer. Via the client software, you can create your notes and add the desired content.
Your notes are hosted online and can be accessed at any time, from any computer or mobile device (smartphone or tablet).
You can access your account settings, to change your email address, passwords, but also to check the status of your storage.
The cost to upgrade from a free to premium account is $5 per month (1 GB storage).