The Gmail service is one of the oldest free email clients available on the Internet. Originally it was by invitation only and each user had a limited amount of invitations to send out to their friends, family or colleagues. Nowadays though, anyone can sign up to use it. Traditionally, it also offered one of the most generous storage, which was many hundreds of megabytes, even gigabytes greater than the major competitors Yahoo! and Microsoft. Right now it offers about 2.5GB in the free service, but this can be increased and is also increasing naturally by itself on a daily basis. People were often using the Gmail service as a storage space.