BIP148 stands for Bitcoin Improvement Proposal 148. It is a user-activated soft fork proposed to help activate the Segregated Witness upgrade for Bitcoin. The main goal of BIP148 is to force the activation of SegWit by a specific date, regardless of whether or not the mining community adopts the upgrade.
BIP148 was introduced as a response to frustrations within the Bitcoin community over the slow implementation of SegWit. By having users enforce the soft fork, BIP148 aims to push miners and nodes to adopt SegWit in order to avoid a chain split.
If miners do not signal support for SegWit by the set date, nodes running BIP148 will reject blocks that do not comply with the upgrade. This could potentially lead to a split in the Bitcoin blockchain, creating two separate chains – one following SegWit rules and another not.
Overall, BIP148 was seen as a way to spur the activation of SegWit and improve the scalability of the Bitcoin network.
