You do have an option of storing the pictures in hard copies but they will wear out with time and can be damaged easily with moisture and wear and tear. Therefore, the best option is to store them digitally.
You need to make several backups of the pictures. A good idea is to share them with all the people depicted in them so that all have a copy. Even if one of the copy is lost, there are many others. Picture sharing with friends and family at social utilities like Instagram and Facebook have enabled us to share with several people at a time. You can tag those present in the picture. The pictures will be conserved with the date and even a description of the event.
Most of us save our pictures on our computer’s hard drive after transferring them. With them, the accumulated size of the pictures increases and there is little memory space left for more. Therefore, it is advisable that you store them in external hard drives and store these drives carefully. Make folders of every event with possible descriptions and save them in these drives. These hard drives can connect to any computer through a simple USB port and can be stored in a plastic bag at a safe location. You can also use thumb and jump drives.
Burn your pictures into a CD or DVD. Both of them are affordable and sustainable options. After saving the photos in them, label them appropriately and store in a safe place